Teaching school physics; UNESCO source books on ... - unesdoc

<strong>Teaching</strong>
School Physics
Edited by John L. Lewis
Penguin Books - Unesco

Penguin Education
<strong>Teaching</strong> School Physics
Edited by John L. Lewis
A Unesco Source Book

Penguin Books Ltd, Harmondsworth,
Middlesex, England
Penguin Books Inc, 7110 Ambassador Road,
Baltimore, Md 21207, USA
Penguin Books Australia Ltd,
Ringwood, Victoria, Australia
United Nations Educational, Scientific
and Cultural Organization,
Place de Fontenoy, 75 Paris 7-e, France
First published 1972
Copyright 0 Unesco, 1972
Made and printed in Great Britain by
William Clowes & Sons Ltd,
London, Beccles and Colchester
Set in Monophoto Times

Contents
1
1.1
1.2
1.3
1.4
1.5
2
2.1
2.2
2.3
2.4
3
3.1
3.2
3.3
4
4.1
4.2
4.3
4.4
4.5
4.6
Preface 11
Editorial Foreword I3
List of Contributors 15
Part One 19
Why Teach Physics? 21
Sir Frederick Dainton 21
A. Babs Fafunwa 23
Denis G. Osborne 26
W. Schaffer 28
Gerald Holton 31
Part T wo Conditions for Learning 41
Basic Conditions: The Nature of Learning 43
Why is science teaching difficult? 43
<strong>Teaching</strong> about science or scientific theory 47
When do we start teaching? 50
Creating optimum situations for learning 51
When to Teach Physics 54
The development of the child 54
Other factors 56
When to teach <strong>physics</strong> 57
Problems of Language in the <strong>Teaching</strong> of Physics 58
Language in advanced modes of thought 58
Generalized concepts 59
Scientific concepts and the language of science 60
The problem of certain languages in teaching science 62
The dilemma for a developing country 63
The need for closer links between language teaching and
science teaching 66

5
5.1
5.2
5.3
5.4
5.5
5.6
5.7
6
6.1
6.2
6.3
6.4
6.5
6.6
7
7.1
7.2
7.3
7.4
8
8.1
8.2
8.3
8.4
8.5
9
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
Part Three Approaches to Content and Method 69
How to Teach Physics 71
Rate of cooling 71
<strong>Teaching</strong> <strong>physics</strong> 73
Learning <strong>physics</strong> 73
The role of mathematics 76
Techniques of teaching 77
Stages of understanding 79
The influence of objectives on how to teach 80
What to Teach: Some General Principles 85
Introductory remarks 85
Educational goals 86
The selection of subject matter 87
Mathematical content of a <strong>physics</strong> course 91
Laboratory work 94
Conclusion 95
What to Teach: The Problem in Developing Countries 96
A plea for an independent outlook 96
The real problem 98
The content of the <strong>physics</strong> course 99
Conclusion 105
Part Four Physics and the Secondary Curriculum 107
Integration 109
Integration and coordination 109
Reasons for integration 109
What makes <strong>physics</strong> relevant to life? 114
Types of integrated course 115
A sample integrated science course 116
The History of Science and its Place in a Physics Course 122
The need for change: the point of view of the
professional scientist 122
The need for change: the point of view of the
professional historian 123
The dangers 124
The present position 124
Educational merits of an historical approach 125
The use of biographies 126
Another danger warning 128
Implementation 130
Conclusion 133

10
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
11
11.1
11.2
11.3
11.4
11.5
12
12.1
12.2
12.3
12.4
12.5
13
13.1
13.2
13.3
13.4
13.5
13.6
13.7
13.8
Physics and Technology 134
Physics and engineering 134
What industry needs 136
A criticism of new <strong>physics</strong>-teaching programmes 137
Motivation 139
Incorporation of technology into <strong>school</strong> <strong>physics</strong> programmes 139
Involvement of pupils 142
Project technology 143
Nuffield advanced-level <strong>physics</strong> 149
Physics and Mathematics 151
Introduction 15 1
What the customer wants 153
The need for collaboration in <strong>physics</strong> and mathematics teaching 154
The structures of elementary mathematics 156
The detailed points of association 157
Physics and Computer Education 161
Introduction 161
Hardware: work with logic circuits 162
Hardware: work with analog circuits 162
Software: programming 164
Software: applications and implications 167
Part Five Learning Re<strong>source</strong>s 169
Physics Apparatus 171
Two notes of warning 171
Cutting costs according to the cloth 173
Apparatus for teaching <strong>physics</strong> 174
Problems peculiar to developing countries 179
Apparatus and curriculum development 181
Local production of apparatus in developing countries 184
Large-scale production 188
Internal cooperation 190

14 Physics Laboratories 191
14.1 Introduction 191
14.2 Laboratories in developing countries 200
14.3 The siting of laboratories 200
14.4 The structure of laboratories 201
14.5 Size, shape and function of laboratories 202
14.6 Ancillary rooms 203
14.7 Storage of apparatus 205
14.8 Services 207
14.9 Laboratory furniture 210
14.10 Lighting, ventilation and blackout 212
14.11 Laboratory organization 213
15
15.1
15.2
15.3
15.4
15.5
15.6
15.7
15.8
15.9
16
16.1
16.2
16.3
16.4
16.5
16.6
16.7
16.8
16.9
Audio-visual <strong>Teaching</strong> Materials 214
Introduction 214
Books 216
Slides and film strips 217
The overhead projector 219
Films 220
Film loops in cassettes 224
Adding sound to visual techniques 225
Radio and television 226
Conclusion 230
Part Six Towards Curriculum Reform 23 1
Mechanisms for Curriculum Reform 233
Background 233
Initiation of reform 234
Local involvement 234
Provision of funds 236
Establishing a science-teaching programme 236
Plan of operation 238
Time factors 240
The kind of course 240
Examinations 241
16.10 Implementation 241
16.11 Involvement of teachers 242
16.12 One method of involving teachers 243
16.13 Summary 243
17 Evaluation and Examinations 244
17.1 Evaluation of a programme of training 244
17.2 Course evaluation 252
17.3 Examinations 262

18
18.1
18.2
18.3
18.4
18.5
18.6
Teacher Education 269
Background to the problem: 1 269
Background to the problem: 2 271
Education of <strong>physics</strong> teachers 275
Pre-service training 276
In-service training 278
Postscript : What kind of teacher training? 280
A
A. 1
A.2
A. 3
A.4
A. 5
A.6
B
B. 1
B.2
B.3
B.4
B.5
B.6
B.7
B.8
B.9
B.10
B.ll
B.12
B.13
B.14
C
c. 1
c.2
c.3
Appendixes 283
Case Histories 285
East African secondary-<strong>school</strong> science project 285
Integrated and coordinated science courses in New South Wales 292
The Nufield programmes in the United Kingdom 303
P S S C and its adaptation for use in Scandinavia 309
The Unesco Pilot Project: follow-up and adaptation in Argentina and
Bolivia 316
New Zealand adaptation of PS S C 323
Details of Various Projects 328
Engineering Concepts Curriculum Project : The Man-Made World 328
Harvard Project Physics 333
Introduction to Natural Science: The INS Project 337
Novosibirsk Project 338
Nufield 0-Level Physics Project 347
Nuffield Combined Science Project 347
Nufield Secondary Science Project 351
Nuffield Advanced Physics Project 354
Nuffield Advanced Level Physical Science Project 362
Physical Science for Nonscience Students: The PSN S Project 366
Portland Integrated Science Project 369
P S S C Physics 374
Course Development Project in Quantitative Physical Science :
the QPS Project 374
Scottish Physics Course 376
Comparative Studies 378
The concept of energy 378
Optics 387
The special theory of relativity 398
References 410
Further Reading 413

Preface
This Unesco <strong>source</strong> book is the second in a series designed to assist those involved
in curriculum planning and development by providing information on new approaches
and experiences, on new methods and techniques in science teaching.
Following closely upon the first book, <strong>Teaching</strong> School Mathematics, this second
<strong>source</strong> book is devoted to a subject of fundamental importance to the advancement
of education and technology - the teaching of <strong>physics</strong>.
Curriculum development considered in its widest sense has been recognized by
Unesco as one of the main generating forces, not only for quality in education,
but also for fostering the ability to assimilate changes, especially those due to the
rapid scientific and technological evolution now in process. Unesco’s programme
to assist member states in science-curriculum renewal has been directed at various
national and local contexts and at different operational levels. The introduction
of a new curriculum necessarily involves the work of many. For this reason, this
<strong>source</strong> book attempts to provide a wide range of ideas and experiences in the
teaching of <strong>physics</strong> for those readers working in <strong>physics</strong> education at various
levels. It is addressed not simply to practising secondary teachers, but also to
curriculum planners, teacher-educators and <strong>school</strong> administrators.
Material is offered on both the theory and practice of teaching <strong>physics</strong> at the
secondary level. While the first chapter raises questions of aims, the following
chapters deal with the content and methods needed to achieve them, with reference
to the particular problems of developing countries. The major part of the
book considers the relationship between <strong>physics</strong> and other subjects in the secondary
curriculum and the problems of implementing curriculum reform, drawing
upon the experience reported in case histories of several current major projects.
This <strong>source</strong> book was prepared for Unesco by John L. Lewis, Senior Science
Master of Malvern College in the UK, in association with the International
Commission on Physics Education. T. D. Miner (USA) and Professors A. S.
Akhamatov and D. M. Tolstoi (USSR) served as editorial consultants. In his
role of general editor of this volume, Mr Lewis is responsible for the presentation
of the various contributions written by scientists and educators in many parts of
the world. The opinions expressed herein are those of the editor and authors and
not necessarily of Unesco.
11 Preface

Editorial Foreword
John L. Lewis, Senior Science Muster, Maloern College
atid U nieniber of the Internutionul Corntnission on Physics Education
A volume containing the work of seventy-three contributors from twenty-six
countries can fairly claim to be international. It is hoped that such a volume,
which attempts to bring together the ideas and range of experience of so many
scientists and educators, wil assist those concerned with curriculum reform in all
parts of the world.
Unesco was anxious that this volume should as far as possible be a unity and
not a series of disconnected papers. To achieve this a somewhat drastic editorial
operation proved necessary and I am extremely grateful to the distinguished contributors
who have accepted this editing with good humour and understanding.
The book is intended to be a <strong>source</strong> book from which teachers, authorities and
those concerned with curriculum reform can draw ideas to improve the teaching
of <strong>physics</strong>. No unique or universal solution to these problems is offered. In fact,
quite often the reader wil find almost diametrically opposed ideas each having
its merits and its shortcomings. The <strong>source</strong> book wants only to encourage and
assist by showing possible ways. Decisions must be made by the particular
country or <strong>school</strong> concerned.
The planning and writing of this volume have been greatly aided by the active
interest and stimulating encouragement of the International Commission on
Physics Education which, under the chairmanship first of Sanborn C. Brown and
then of Hans H. Staub, has appreciated the importance of <strong>physics</strong> teaching in
the secondary <strong>school</strong> as well as concerning itself with the problems of teaching
at university level.
1 am also deeply indebted to the staff at Unesco in Paris for their unfailing
help and support. Finally, I must place on record my gratitude to the editorial
consultants. Thomas D. Miner, A. S. Akhmatov and D. M. Tolstoi, who have
always been willing to help ungrudgingly whenever called upon to do so.
13 Introduction

List of Contributors
A. S. Akhmatov Moscow Machine-Tool Institute, Moscow, USSR.
Meir Avigad Ministry of Education and Culture, Jerusalem, Israel.
A. V. Baez Consultant, Office of Science and Technology,
United Nations, New York.
S. T. Belyaev Physics-Mathematics School, Novosibirsk University, USSR.
M. Y. Bernard Conservatoire National des Arts et Mktiers, Paris, France.
E. I. Bichenkov Physics-Mathematics School, Novosibirsk University, US S R.
P. J. Black Birmingham University, UK.
Norman Booth HMI, Department of Education and Science,
London, U K.
Sanborn C. Brown Massachusetts Institute of Technology, Cambridge,
Massachusetts, US A.
Stephen G. Brush University of Maryland, Maryland, USA.
Jerome S. Bruner Harvard University, Cambridge, Massachusetts, US A.
David C. F. Chaundy Malvern College, Malvern, Worcestershire, U K.
B. V. Chirikov Physics-Mathematics School, Novosibirsk University, USSR.
S. Winston Cram Kansas State Teachers College, Kansas, US A.
Frederick Dainton Oxford University, UK.
G. Diemer Philips Research Laboratories, Eindhoven, Netherlands.
Geoffrey W. Dorling Worcester College of Education, Worcester, U K.
Peter E. Dutton Sheffield Polytechnic, Sheffield, UK.
Joseph Elstgeest Morogoro Teachers College, Morogoro, Tanzania.
Maurice J. Elwell City of Birmingham College of Education,
Birmingham, U K.
A. Babs Fafunwa University of Ife, Ile-Ife, Nigeria.
Rafael E. Ferreyra University of Cordoba, Argentina.
Michael Fiasca Portland State University, Oregon, US A.
A. P. French Massachusetts Institute of Technology, Cambridge,
Massachusetts, US A.
K. G. Friskopp Ministry of Education, Orebro, Sweden.
A. W. Fuller HMI, Department of Education and Science,
London, U K.
T. L. Green University College, Cape Coast, Ghana.
15 List of Contributors

G. B. Harrisop College of Education, Loughborough, UK.
I. E. Ginzburg Physics-Mathematics School, Novosibirsk University, USSR.
K. Hecht Institut fur die Pedagogik der Naturwissenschaften,
Kiel, Federal Republic of Germany.
N. E. Heath Teachers Training College, Christchurch, New Zealand.
R. J. Heller FacultC des Sciences de Paris, Paris, France.
H. Helm Rhodes University, Grahamstown, Republic of
South Africa.
Gerald Holton Harvard University, Cambridge, Massachusetts, US A.
Kevin Keohane Chelsea College of Science and Technology,
London, U K.
L. S. Kothari University of Delhi, Delhi, India.
John L. Lewis Malvern College, Malvern, Worcestershire, U K.
R. Lewis Chelsea College of Science and Technology,
London, UK.
D. D. Lindsay Malvern College, Malvern, Worcestershire, U K.
V. J. Long East African Science <strong>Teaching</strong> Project, Kenya.
C. B. A. McCusker University of Sydney, New South Wales, Australia.
F. R. McKim Marlborough College, Wiltshire, UK.
R. F. Melton Ford Foundation, Dacca, Pakistan.
Harry Messel University of Sydney, New South Wales, Australia.
Maurice Milbourn formerly, Imperial Chemical Industries, Metals
Division, Birmingham, U K.
Thomas D. Miner Belfer Graduate School of Science, Yeshiva University,
New York, USA.
Mrs H. Misselbrook Nuffield Secondary Science Project, Chelsea College of
Science and Technology, London, U K.
Erasto B. Mpemba Game Division, Dares Salaam, Tanzania.
R. G. Munro Secondary Teachers College, Auckland, New Zealand.
L. Nedelsky University of Chicago, Illinois, USA.
G. C. Norman Milton Margai Teachers College, Freetown,
Sierra Leone.
J. M. Ogborn Nuffield A-level Physics Project, Chelsea College of
Science and Technology, London, UK.
H. Ootuka Nippon Optical Academy, Tokyo, Japan.
D. G. Osborne The University, Dar es Salaam, Tanzania.
V. L. Parsegian Rensselaer Polytechnic Institute, Troy,
New York, USA.
Isais Raw Fundacao Brasileira para o Desenvolvimento,
Sao Paulo, Brazil.
W. R. Ritchie Scottish Education Department, Edinburgh, U K.
W. Schaffer University of Cape Town, Rondebosch, Republic of
South Africa.
R. W. Sillars GEC/AEI Power Group Research Laboratory,
Trafford Park, Manchester, UK.
16 List of Contributors

J. E. Spice Winchester College, Hampshire, UK.
H. H. Staub Physik-Institut der Universitat Zurich, Zurich,
Switzerland.
Peter Strevens University of Essex, Colchester, UK.
J. Thomson Sangamo Weston Ltd, Enfield, Middlesex, UK.
Bryan Thwaites Westfield College, London, UK.
D. M. Tolstoi Moscow Machine-Tool Institute. Moscow. USSR.
G. van Praagh Centre for Educational Development Overseas,
London, UK.
J. Volger Philips Research Laboratories, Eindhoven, Netherlands.
Fletcher G. Watson Harvard University, Cambridge, Massachusetts, US A.
E. J. Wenham Worcester College of Education, Worcester, UK.
Patrick A. Whittle National Teachers College, Kyambogo, Uganda.
J. G. Wilson Leeds University, Leeds, UK.
Stephen Winter State University of New York, Buffalo,
New York, USA.
M. K. Woolman Makerere University, Kampala. Uganda.
17 List of Contributors

Part One

I Why Teach Physics?
The reasons for teaching <strong>physics</strong> may be cultural or economic, national or personal.
Some wil teach <strong>physics</strong> nerely because they enjoy doing so and find it intellectually
satisfying. For a country such as Singapore, which has a population of nearly two million,
but an area of less than 250 square miles. the reasons are primarily economic: they must
have more scientificallytrained manpower for their economy to survive.
In this chapter, unlike most other chapters in thisvolume, the contributions appear
as a sequence of papers. They reflectthe personal views of the authors and to some extent
the needs of the countries from which they write.
The first comes from Sir Frederick Dainton, who as Vice-Chancellor of Nottingham
University was chairman of the committee which produced the ' Dainton Report' on the
flow of candidates in science and technology into higher education. The second is from
Professor A. Babs Fafunwa of the University of Ife, the third from Professor Denis
G. Osborne of the University of Dar es Salaam. The fourth expresses the views of
Professor W. Schaffer, a member of the International Commission on Physics Education.
The finalcontribution is a shortened version of an historic paper by Professor G. Holton
of Harvard University, given at the Conference on Physics in General Education
organized by the International Union of Pure and Applied Physics in Rio de Janeiro
in 1963.
1.1 Sir Frederick Dainton
No doubt others, like myself, see a pleasant and gentle irony in the situation in
which a chemist should write in response to a rhetorical question 'Why teach
<strong>physics</strong> ?'. However, on reflection an even-handed logicality can be perceived.
On the one hand we recognize <strong>physics</strong> as essentially the atomic science and
chemistry the molecular science, and the study of molecules is impossible without
an understanding of atoms, either in isolation or in assemblies. In this sense
chemistry can be said to rest on the theoretical and experimental base provided by
physicists. Any doubts about this question would rapidly be dispelled by a
perusal of any current chemical journal, from which it would quickly be apparent
that not only do chemists increasingly rely on physical methods for the elucidation
of structure but also that physical concepts increasingly provide the language
by which chemical change itself is best expressed.
On the other hand, <strong>physics</strong> and chemistry are each parts of a body of knowledge
which used to be called, and in some institutions is still called, natural
21 Sir Frederick Dainton

philosophy or natural science. To understand existing knowledge, and if possible
to add to it, has always been one of the aspirations of homo sapiens. His motives
have not always been the same. Sometimes, as with embryo technologists like
Wedgwood, it has been to improve the useful arts; for others, like the early
engineers Watt, Brunel and Marconi, it was to design a machine, structure or a
process to enable man to do things hitherto denied him. Even Thomas Carlyle
saw in man’s capacity to apply knowledge a characteristic of immense significance,
for in 1833 he made Professor Teufelsdrock in Surtor Resurtus say:
Man is a tool-using animal. Weak and of small stature, he stands insecurely enough on a
base of at most half a square foot. He has to straddle out his legs lest the wind blow him
over. He is the feeblest of bipeds. Three quintals are a crushing load for him; thesteer of the
meadow tosses him aloftlike a waste rag. Nevertheless he can use tools, he can devise tools.
With these the granite mountain melts into light dust before him, seas are his smooth
highway, and wind and fire his unwearying steeds. Nowhere do you find him without
tools. Without tools he is nothing, with tools he is all.
But lying much deeper in his being than a desire to master nature and use her
for his own purposes is man’s curiosity. This impels him to learn about the external
world because he knows, almost instinctively, that the knowledge he wil gain
will allow him to know more of his own relationship to that world and in so
doing to discover more about his own identity. Of all subjects in science perhaps
<strong>physics</strong> offers the greatest opportunity for discoveries of fundamental philosophical
importance, since only through it can an understanding be gained of
those primal forces which, to give only two examples at extremes of distance,
govern the interaction of celestial bodies at billions of metres separation and of
nuclear constituents at about 10- metre separation.
Science is unique in simultaneously offering to man the means both to control
and exploit the forces and re<strong>source</strong>s of nature and to elicit more about the meaning
and purpose of his life.Physics lies at the heart of science. Why then is the
study of <strong>physics</strong> and science not universally regarded as a ‘good’ activity but, in
fact, has come to be viewed with some alarm and suspicion? Mutterings of the
early sixties that ‘the scientists are out of control’, that ‘science creates more
problems than it offers solutions or benefits’, that ‘our genetic inheritance can
now be manipulated’ and so on, have grown in volume in this decade.
This mood, which is now rather pervasive in developed western countries, is
extremely dangerous ; the truth is that careful, painstaking and methodical study
of the problems created by past thoughtless and too often rapacious exploitation
of the earth and oceans shows beyond doubt that the solutions to these problems
are only to be found by thoughtful and humane application of more science.
Whether society wil be able to choose between ‘good’ and ‘bad’ future applications
of science will depend upon the capacity of citizens to appreciate the
issues, and for this they need to be aware of the power and limitations of scientific
methods. Moreover, since the forces of nature are no respecters of territorial
boundaries, these choices cannot, to the same degree as in the past, be made
purely in interests of a particular locality or community, but must increasingly be
22 Why Teach Physics?

made with regard for possible future consequences at any other point on this
planet and therefore be internationally acceptable.
The question ‘Why teach <strong>physics</strong>?’ is therefore especially important at the
present time. The answer is partly traditional, namely that it is an essential part of
man’s nature, which cannot be denied, to seek to know more of nature and so to
learn more about himself, and that this knowledge gives him greater power over
his own destiny. This power is already so large that society must be educated to
understand more of its nature and the options which it presents between which
choices must be made. If education is not achieved the choices are likely to be less
wise and the alienation of those for whom the scientific method is, and wil
remain, a mystery wil inevitably grow. W e cannot afford permanent humiliation
of part of society, a humiliation which arises from the lack of understanding
which most people have of contemporary science because as scientists we have
failed to teach them adequately. Therefore to our traditional task of educating
professional scientists are added two other duties : first, to ensure that developed
countries have a scientifically educated rather than a scientifically deprived
people; and second, to help those in developing nations to avoid the errors of
omission and commission which we have made. Perhaps a chemist may therefore
answer the question ‘Why teach <strong>physics</strong>?’ by suggesting that the more pressing
question is ‘How can <strong>physics</strong> be taught better to more people in ways more
relevant to their needs?’.
1.2 A. Babs Fafunwa
We are living in a world where science and technology have become an integral
part of the world’s culture, and any country that overlooks this significant truism
does so at its own peril.
It is our contention that it was the practical application of the new discoveries
in science and technology that was largely responsible for transforming the erstwhile
underdeveloped or backward societies of the West into advanced states.
It was also because of the speed with which these new phenomena were disseminated
and proliferated that the West was able to gain a substantial lead over
the rest of the world. It was the study of such phenomena as mechanics, vibrations,
acoustics, hydrodynamics, molecular <strong>physics</strong>, including elements of thermodynamics,
electricity, optics, atomic <strong>physics</strong>, and the more recent studies of
solid-state <strong>physics</strong>, low-temperature <strong>physics</strong> and the <strong>physics</strong> of magnetic phenomena,
which went a long way to bring economic and social benefits to mankind
in general and to Europe and America in particular. These guaranteed them a
high standard of living and improved the health of their people.
It would therefore be foolhardiness on the part of the non-Western countries
not to recognize science and technology as a dominant cultural factor in this
late twentieth century. Dissatisfied with their own rate of growth. both Europe
and America continue to seek newer ways of doing things; yet many of the first
fruits of scientific and technological progress have not yet arrived in Africa and
Asia and the new advances which have superseded the old are even further from
Africa’s reach.
23 A. Babs Fafunwa

It is possible to exist with little or no knowledge of science. Indeed, millions of
people in developing countries do just that. But it is almost impossible today to
lead a full and satisfactory life with little or no knowledge of science. Nigeria and
other underdeveloped countries must develop their human and natural re<strong>source</strong>s
to solve their economic problems. They need to improve their diet, improve their
transport system, develop their mineral re<strong>source</strong>s and control soil erosion. They
must introduce modem scientific farming, control cattle diseases, improve their
health programme and solve a myriad of other problems that call for scientific
and technological dexterity. To achieve this they must, as a matter of national
urgency, train as quickly as possible an army of competent and complete scientists,
technicians and teachers. They require also scientifically and socially orientated
policy makers, as well as scientifically orientated citizens. Science in the
twentieth century has without a doubt become a necessary aid to good living
and good citizenship, to health, agriculture, home making and leisure. For these
reasons, therefore, science and technology must necessarily play a vital part in
Nigerian education and the new <strong>school</strong> curricula. Every child, every future adult
has to be reached.
To achieve this, foundations must be laid at all levels of education through
both general and special education. By general education, in this context, we
mean a broad type of education aimed at developing the attitudes, abilities and
behaviour considered desirable by society. As far as science and technology is
concerned, it is attitudes that matter. It is largely through adopting a scientific
approach to problems that Africa can join a world where science has already
become a dominant cultural factor. Given this desirable scientific attitude in the
African, a successful war could be waged against superstitition; aptitudes could
be developed for vocational pursuits; the child and the adult would be able to
manipulate simple gadgetry, work of hand and eye which would buttress or supplement
mind and heart. It is most essential that Africans should develop this
scientific attitude in agriculture, still the occupation of over 70 per cent of the
people.
Unfortunately, no major industrial revolution can either take place or be sustained,
no new society can be built or maintained in a continent where the masses
are still dominated largely by magic and superstition.
Superstition and belief in magic perhaps claim as many lives as most curable
diseases. There are many cases in Africa where the health officer or inspector
whose duty it is to discourage charms and rid the community of water-filled and
mosquito-infected native medicine pots is himself in possession of such charms
and other concocted devices to enable him to ward off evil spells or to cure his
own family’s illness. There was a celebrated case of an English-trained Nigerian
magistrate who had to ‘clear the court’ because someone within the court
premises was in the process of using some charms on him with a view to perverting
justice. It is not uncommon to find some well-qualified professionals in
African society who believe in witchcraft or sorcery.
This type of cultural ambivalence can be easily explained. It is due to the fact
that the African is a man of two worlds; that of African culture and that other
24 Why Teach Physics?

world where science has already become a dominant cultural factor. The African
is operating in both these worlds as best he can. Any individual faced with a
similar problem anywhere would possibly respond in the same way as the
African, especially if that individual were not adequately prepared to cope with
these conflicting realities of life. It has been erroneously alleged by some writers
that the average African either is incapable of the scientific attitude or that it wil
take him countless generations to acquire it as a form of logical reasoning, using
as one argument the fact that the idea of the ‘wheel’, the simplest and the oldest
scientific device, was unknown to him. This is bad reasoning, because the wheel
was certainly known in early Egypt.*
It is accepted by most educators that knowledge is not inborn or inherited.
Science and technology in particular are the products of challenge and response,
unlike art and literature, which are the products of creative leisure and artistic
instinct. The scientific attitude can be acquired as a way of life in the same way as
socialism or capitalism, communism or the Christian life are injected into society
as a way of living.
The crux of the matter is still the promotion of the scientific attitude. The most
important means for achieving a built-in scientific attitude is through the curriculum
as it relates to the formal education of the young and the informal
education of the adult. Next in importance are the teachers, through whom the
primary-<strong>school</strong> children, the high-<strong>school</strong> leavers and the university graduates,
the newly literate and even the non-literate adult can share at least in some
degree part of the vast knowledge which science and technology have placed at
the disposal of man. In this way the existing world of science can be brought
within reach of the average African, the gap between Africa and the rest of the
world can be reduced and Africa can exchange her role as a spectator in the
world and become an actor in this scientific age.
But one may ask what are the scientific attitudes which must be transmitted.
A scientifically orientated person must have curiosity. manipulative ability and
mechanical comprehension; good spatial visualization; adaptability and spontaneous
flexibility; initiative, concentration, industry and enthusiasm; the ability
to plan, design and conduct investigations. This list is not exhaustive, but it gives
a general idea of what qualities must be encouraged in order to produce a scientific
attitude.
No doubt the African is already endowed with some of these attributes, but
what is absent is an organized systematic education to develop and integrate
these characteristics in order to ensure persistent, dynamic application of a
scientific attitude towards the material world.
The elementary curriculum should depart radically from the conventional
curriculum found in many Western countries. Pupils should be introduced to
* ‘The wheel was probabiy invented in Sumeria before 3000 B c. Use of the wheel spread slowly and was
(probably) not much used in Egypt till about a thousand years later. So far as is known. no other people
than the Sumerians ‘invented’ it. It reached Britain perhaps around 500 BC: two-and-a-half thousand
years after its invention. Africans need never feel ashamed that they had to borrow it ~ they are in good
company.’ ~ Professor Schaffer.
25 A. Babs Fafunwa

physical and biological science from the first year of the primary <strong>school</strong>. The
child should be introduced to the simple principles of mechanics - the lever,
wheel, pulley, pump, friction, gravity and so on. He should be taught about cloud
and rain formation, the difference between plants and animals, and the composition
of water. He should learn about air, sound, waves and echoes, reflection and
refraction, and the many other phenomena which are already part of his immediate
experience.
Considerable emphasis needs to be placed on science at the elementary level,
because for the next fifty years or more most African countries will not be able to
provide more than a free elementary education for their people. Consequently,
millions of future African citizens, who will form the bulk of Africa’s manpower,
will not have more than a primary education. It follows, therefore, that this new
generation of citizens should have more scientific background at this elementary
level of education than the Western counterpart at the same level.
A typical elementary-<strong>school</strong> curriculum in Africa should be restricted to three
areas : reading and writing, science and mathematics, civics and health. Science
should form a third, or preferably half, of the elementary-<strong>school</strong> work.*
Advisers and planners often argue that since Africa is one mighty biological
garden and Nigeria, like most African countries, principally an agricultural
country science education should place greater emphasis on biological studies.
This is unrealistic for two reasons. First, Nigeria will not remain agricultural indefinitely.
Secondly, the physical sciences lend themselves more easily to the
development of a scientific attitude and the skills such as those already listed
earlier in this paper. Japan and the US S R are two remarkable examples of how a
technologically-backward country can be transformed from a predominantly
peasant and agrarian economy to a technologically modern state.
In the area of physical sciences, therefore, <strong>physics</strong> education is a sine qua non
for a country like Nigeria which is struggling to join a world where science and
technology have become a way of life.
1.3 Denis G. Osborne
Why teach <strong>physics</strong>? In particular, why teach the subject in secondary <strong>school</strong>s of
the newly developing nations? To attempt an answer requires an assessment of
the role of education in a developing country and some concept of the nature of
<strong>physics</strong> as a subject of study.
1.3.1 The context
In Tanzania there is a policy of ‘education for self-reliance’. It is recognized that
the country needs manpower at all levels. It is also true that after each level of
education more students take up careers than continue with full-time education.
For the majority of those leaving secondary <strong>school</strong> those careers are on the land.
In the past, secondary education has led to office jobs in the cities, but with the
* The idea expressed here will be found elaborated in Fafunwa (1967).
26 Why Teach Physics?

expansion of secondary education in a country having an agricultural base the
role of the secondary <strong>school</strong> must change. Secondary education must be planned
for the benefit of the many who wil end their formal education at the <strong>school</strong>certificate
level after four years in secondary <strong>school</strong> rather than for the few who
will continue to university. It must prepare students for life and work in rural
society.
In the villages little has changed with the years, for the dramatic aspects of
initial development have been centred in the towns. Yet in all developing countries
the great majority of the population live in small villages. Agriculture will
remain the largest <strong>source</strong> of employment and the most important factor in the
economy for several decades. Even modest changes in farming techniques may
bring great gains. In development the future is indicated less by the present rate of
change than by the rate of change of the rate of change. It is the second differential
that matters!
It is a recognized feature of the world scene that societies are being transformed
within less than one human lifetime. It follows that education should, somehow,
prepare men and women for lives of continued learning and adaptation to
change. (I suspect that much curriculum reform of the ‘think for yourself’ type is
welcomed, knowingly or unknowingly, because it is appropriate to a rapidly
changing society.) Secondary-<strong>school</strong> leavers in the developing countries need to
be specially versatile. They should be content to leave <strong>school</strong> and return to life
in a simple rural society; they should be able to adapt to rapid and drastic changes
in technology and in social structure; but they should be sufficiently dissatisfied
with the situation (in which they agree to live) to be themselves the agents of
change.
1.3.2 The subject
Physics encourages certain attitudes and carries a specific inforniation content.
Some of these attitudes and parts of the information are specially relevant to a
developing society.
First there are the attitudes. (a) Physics requires a methodical study that is
characteristic of all the sciences. But it is possible to choose more simple systems
in <strong>physics</strong> than in other fields, so that the basic methods of study and their success
can become apparent to students at an early age. The ideas of models and of
abstract concepts can be introduced. (b) Physics illustrates also the cumulative
character of scientific thought, showing how new concepts develop from the old.
(c) Physics generates an openness to new ideas that offers good preparation for
life in a world of rapid change. Even at the secondary-<strong>school</strong> level there is abundant
evidence that things are not what they seem. Surprise and wonder can come
from astronomical distances or the atomic character of matter and electricity.
Provided the arguments are presented and the facts are not stated as a dogma,
the discovery that things differ from common-sense expectation can lead to
scientific humility and intellectual versatility. (d) Physics is concerned with identifying
problems and then arriving at solutions to them. This emphasis on
27 Denis G. Osborne

problem-solving is an important training for life, especially in showing how important
it is to ask meaningful questions.
I would like to add here my own opinion that it is the study of <strong>physics</strong> itself
that brings these hidden gains to a student. Probably it is good that the teacher is
aware of them, but I think it is not good if they are mentioned often during the
course. The student learns his scientific methodology through grappling with the
subject, not by studying scientific method (about which much nonsense has been
written). These gains in attitude come from studying <strong>physics</strong>, not from studying
the study of <strong>physics</strong> by others.
The subject matter of <strong>physics</strong> has an obvious relevance to workers in many
different fields. It is basic to ‘both sides’ of the applied sciences, needed on the
one hand by future technicians and engineers and on the other by future doctors
and dentists, pharmacists and agricultural officers.
To name but two, the farmer and the builder do work of concern to everyone
in a rural community. If they have developed an enquiring mind and have gained
a measure of basic scientific knowledge, they can be expected to do a better job
and to be more open to innovation in consequence of their training. More than
this, genius will not always reveal itself in the early years: some who leave <strong>school</strong>
without entering university may have the inventiveness to suggest new solutions
to old problems. One of the human qualities most needed for development is that
of enterprise. Ideally this should be based on sufficient knowledge to generate
relevant ideas, but not so much as to stifle innovation!
If these are the main reasons for teaching <strong>physics</strong> in a developing nation, the
<strong>physics</strong> curriculum ought to take account of them. Basic concepts, common to
<strong>physics</strong> taught everywhere, are essential. But illustrations and applications
should be drawn from the students’ environment and for this reason imported
text<strong>books</strong> are seldom really suitable. In large measure <strong>physics</strong> can be introduced
as a field science. For example, the weather, heat and humidity can serve as an
introduction to the study of gases and vapours. Local applications abound, in
simple tools, building techniques and materials, irrigation, bicycles and cars, and
the ubiquitous transistor radio.
While preparing this answer to ‘Why teach <strong>physics</strong>?’ I asked a small group
of Tanzanian students for their views. One stressed the desire of young students
in the secondary <strong>school</strong>s to explain their experiences: ‘The car skids and we ask
why.’ Another saw <strong>physics</strong> providing some compensation for a weak technological
background and thus preparing students for entry to a new era. There was
reference to the need.for knowledge so that one could not be fooled by the visiting
expert or adviser. One student said that African students must grasp the basic
principles and then develop the ideas in their own way. Thus the science and technology
of the developing nations wil not just be copied from that of other
nations but will make its own contribution to the world.
1.4 W. Schaffer
The question ‘Why teach <strong>physics</strong>?’ is basic and the answers to what, when and
how depend upon it. For clearly what we teach, how we present it and to whom,
28 Why Teach Physics?

can only be decided when we know what we are trying to achieve. Here we need to
be careful: most of us teach <strong>physics</strong> because that is our job and we try to find good
reasons for what we are doing. These reasons may be mere rationalization and
no more convincing than some of the reasons which classics teachers used to give
some years ago to justify the inclusion of Latin in <strong>school</strong> curricula. We should
also remember that students are demanding that their studies be relevant, relevant
to the kind of life they are likely to lead and to the society in which they wil
have to live and earn their bread. And many do not approve present-day forms
of society and are involved in discussions (sometimes more than discussions) on
how to change the structure of their society. If this were only a passing fashion
we could well ignore it. but what if it is deeper than that and if it is based on a confused
awareness that we have somehow gone astray and that society as it is does
not meet human needs?
The world is largely technological, based on large-scale industry with its
intricate organization and with a complicated interdependence of factory on
factory, mine or field, involving many countries. The individual usually knows
only his own area of work, and feels that he has become a blind and impersonal
labour unit in a vast machine. At other levels, white-collar workers and even
technologists and applied scientists are also not always satisfied with conditions.
Science is more often blamed for this situation than it is praised for making possible
the greatly improved standards of living and of education in some countries,
and the subsistence of larger populations in some others. Briefly, many are
today more concerned with men than with things; they want to improve ways of
living together in the new technological environment and feel that this is more
urgent than introducing yet more technical advances. This is probably part of the
reason for the drift from the physical sciences in a number of countries.
It is against this background that the question (and it is a question) ‘Why
teach <strong>physics</strong>?’ should be answered. There are several answers and while all are
valid their relative importance has very different emphasis in different countries.
1.4.1 Deoelopiiig couiitries
Consider first a ‘developing country’. The standard of living must be raised.
There must be more <strong>school</strong>s, more roads, more hospitals, better food. All these
require more efficient agriculture and the establishment of industries. Some
education in <strong>physics</strong>, as the basic experimental science, is essential in order to
train technicians, engineers and doctors.
Perhaps even more important than the knowledge which directly underlies the
use of technical equipment in industry, and the application of more effective
methods of farming, is that enlightenment which allows objective thinking and
the association of cause with effect to replace superstition and belief in magic.
This process took centuries in Europe and is still not complete. Only three-and-ahalf
centuries ago as great a man as Kepler was strongly influenced by ideas and
beliefs which today appear strange and, when seen somewhat arrogantly from
the twentieth century, even nonsensical. Freedom from superstition is not a godgiven
attribute ofamythical European mind; it is the fruit of centuries of scientific
29 W. Schaffer

labour and education, stimulated in Europe by a complex of circumstances.
People in developing countries cannot wait for a slow development on this historical
model, nor is this necessary. The process should be designed to be hurried
over within perhaps two generations and the <strong>physics</strong> taught (as part of a general
education) should be planned accordingly.
It is less important for these countries to produce a few distinguished scientists
than it is to raise the general level of education and to train technical men for
industry and agriculture. So the <strong>physics</strong> taught should be designed to show how
facts are established by experiment and observation, how generalizations are
built upon this knowledge and concepts developed, and how theories are tested
in the laboratory. Skills can come later, extensive knowledge is not essential, and
specialized training and research can be left (as in more developed countries) to
the few. There should probably be a very special emphasis on the <strong>school</strong> laboratory.
This kind of <strong>physics</strong> in this environment has clear social value; it is ‘relevant’
and its teaching fits in with what young people can see as part of their
service to their fellow man.
1 A.2 In more developed countries
In more developed countries the situation is different, though only in the distribution
of emphases. There is perhaps less need to combat prevailing superstitions,
less need to impart an acquaintance with machines and simple electrical
devices, for these will in any case be familiar to most pupils. But the popularity of
such follies as astrology shows that superstition is not dead, and a look at some
of our newspapers, or half-an-hour listening to a commercial radio programme,
will make us wonder just how advanced people in developed countries really are!
Nevertheless there is a difference of degree. A child who has used mother’s
washing machine or helped father to replace a fuse or repair his car, who sees
newspaper pictures and descriptions of aero-engines and of moon flights, can
study and enjoy an appropriate course in <strong>physics</strong>. He will probably have spent
several years of early childhood playing with mechanical and constructional toys
and with ingenious working models of sophisticated equipment. So he should be
able to understand more abstract concepts and wider generalizations at an earlier
age. There need be less explicit emphasis on thinking objectively, less also on
skills, and instead an earlier approach to deeper intellectual interests. These include
the desire, in some even the need, to be able to interpret the world. We want
unified laws which make things around us intelligible and which excite our
imaginations to invent or explore, and to assemble the elements of our knowledge
into new patterns. Pupils at this intellectual level will, of course, be found
in all countries, and should receive an education fitting their abilities and their
interests. But in the less developed countries it is more urgent to provide elementary
and medium-level education for large numbers, even if gifted students have
for some years to be sent to foreign <strong>school</strong>s or universities for advanced training.
In advanced countries an education in simple <strong>physics</strong> (as in some other disciplines)
is being provided in the home, the street and in the <strong>school</strong>. We want to
30 Why Teach Physics?

give to many others the <strong>physics</strong> they need to understand their world better and to
help them to greater skill in future occupations.
A smaller number we need in addition to train as future scientists. What
<strong>physics</strong> to teach, and how to present it to these future scientists. is largely a technical
matter and one on which most scientists probably hold strong views. Some
may teach too much and spoil the freshness and originality of young minds by
imposing an overload of other men’s work, and some may teach too little and
send out young scientists ill-prepared for research, but most succeed in training
good physicists. Our concern is, then, less with these than with the many, who
wil never be physicists, but who are less than full men without knowing any
<strong>physics</strong>. We should reconsider well-known phrases like those I have used above
and other hackneyed ones such as ‘<strong>physics</strong> and society’. They do not mean anything
very clear. What do we mean when we use them?
1.4.3 Physics and society
We feel a need to understand our world, to see order in what is at first complicated
and confusing, to be able to use our knowledge to provide ourselves and our
neighbours with food, shelter, transport, amusement. and interest and safety.
Some of that world concerns our relations with other people, classes. nations and
groups. Part of that world concerns literature, art and music. But we are concerned
with understanding the material foundation, matter and energy in their
many forms and interactions, on which all life is built. This understanding, in so
far as it has been attained, is <strong>physics</strong>. Our knowledge of <strong>physics</strong> has produced
industry, tools and devices, and new forms of transport, as well as new means of
destruction. Our knowledge of <strong>physics</strong> has been gained by men, each working in
his own historical period. This <strong>physics</strong> has affected thought in other spheres and
through technology has revolutionized peaceful industry and methods of war. It
has shaped history. These are some of the reasons why <strong>physics</strong> should be part of
education at the secondary level.
1.5 Gerald Holton*
In his speculative essay, The Rule of Phase Applied to History, dated 11 January
1909, the American historian, Henry Adams, came to a remarkable conclusion :
‘ . . . the future of thought, and therefore of history, lies in the hands of the physicists,
and. . . the future historian must seek his education in the world of mathematical
<strong>physics</strong>. A new generation must be brought up to think by new methods,
and if our historical departments in the universities cannot enter this next phase,
the physical department wil have to assume the task alone.’
In arriving at this startling view, Henry Adams explains that he was guided by a
desire to transfer to the study of history some of the conceptions developed in
* This contribution is a shortened version of Holton (1963): it forms the basis of the philosophy behind
Harvard Project Physics (see Appendix B.2).
31 Gerald Holton

1876-8 by Willard Gibbs, Professor of Mathematical Physics at Yale, in his
famous paper Equilibrium of Heterogeneous Substances, and by other physicists
and chemists who followed him. Just as Storey saw in the phase rule a means for
putting into hierarchical order the sequence of ‘phases’ consisting of solid, fluid,
gas, electricity, ether and space, so did Adams believe that thought, too, in time
passed through different phases. Adams found confirmation of his essentially
prophetic and apocalyptic view that history obeys quasi-physical laws in the
apparently increasing rate of change of historical processes, and he thought
they were analogous to the increasing motion of objects which are attracting one
another by an inverse-square force or to increases in the rate of other physical
effects.
I have cited this not because physicists would believe that history obeys laws
closely analogous to those of <strong>physics</strong>; rather I have spoken about Henry Adams
because, as usual, he had brilliant insights in this essay, primarily on two counts.
He saw that the ideas emerging from <strong>physics</strong> would continue to be, as they had
again and again been since the early seventeenth century, a central part of modern
culture; and second, he saw that science is both a major mechanism for change in
culture as well as a way of understanding the change better.
Today, we would like to believe that these insights are generally shared by all
men who have thought about the matter. Thus the chairman of the National
Commission of College Physics (1962) in the USA has said: ‘The recognition of
the role of physical science as a chief determinant of our culture, and the recognition
of <strong>physics</strong> as a discipline having many of the educational values associated
with the classics in the nineteenth century are contributing to this trend.’
And in a completely analogous way A. S. Akhmatov of the US S R stressed the
basic place of <strong>physics</strong> in the general cultural requirements of educated men and
women when he wrote (Akhmatov, 1960) :
It is clear at present to everybody that it is precisely the progress of <strong>physics</strong> that determines
the possibilities of development in a very wide range of sciences, from cosmology to
biology and medicine. It is <strong>physics</strong> that determines to a large extent the foundations of our
outlook as well as the possibilities and limits of our practical activities. One cannot be
called a specialist or, for that matter, an educated person unless one is familiar with a
certain range of ideas and factsin the sphere of <strong>physics</strong>.
This is by no means generally agreed outside the circle of physicists. There are
two main groups ~ not to mention the philistines who have always viewed any
intellectual activity with suspicion - that would deny the proposition that <strong>physics</strong>
has one of the central positions in our culture. One represents, as it were, the
reaction of the right, from the side of misguided traditionalism. They would say
with Matthew Arnold that ‘culture is, or ought to be, the study and pursuit of
perfection’ and would then define the properties of perfection ~ for example,
beauty and intelligence -in such a way that most scientific work stands exposed
and condemned as soulless hackwork and the manipulation of trade-<strong>school</strong>
mechanics. Or with T. S. Eliot they would say that culture and religion are ‘different
aspects of the same things’, and then, instead of noticing that science is also
32 Why Teach Physics?

an ‘aspect of the same things’, they would define culture and religion in such a
way that science, when it is mentioned at all, becomes identifiable with idolatry.
That such feelings are not confined to intellectuals has been shown in surveys in
the United States (O’Down and Beardslee, 1961).
A revealing quotation from an editorial in the English Sundq Telegraph of
11 March 1962 provides evidence for this point as clearly as we can wish:
A free and prosperous society depends on the activities of three distinct classes: a political
elite trained by the study of the humanities to take broad, enlightened views about ends
and means, a technical elite willing to exercise its skill in obedience to the community’s
will, and a proletariat with enough mechanical intelligence to respond to managerial
direction.
The first of these conditions has not yet been entirely removed by the renunciation of the
classics, the second will be secure so long as scientists are not encouraged by dabbling in
the humanities to develop a wish to govern society, and only the third . . . is strikingly
absent.. . .
The other, or left-wing, opposition comes from the ranks of science itself.
A relatively small but influential proportion of scientists would say that there
simply is no meaning in the proposition that <strong>physics</strong>, for example, is anything
more than what they and their best associates are actually doing at the blackboard
or in the laboratory here and now. Unlike the first group of opponents,
who object that science has little place in culture, the second objects that culture
has little validity compared to science. Only politeness prevents them from dismissing
with vocal impatience the suggestion that there are valid and important
links between what happens in the laboratory now and what happens, has happened,
and wil happen elsewhere - in the sculptor’s studio, on the stage, in the
court-room, in the study of a philosopher or an economist. and even in the
nursery where a child is asking his mother for help in making sense out of the
world around him. And the major reason why some of these scientists can neglect
the complex, tenuous, long-range links that attach to their science is that
they are so successful in doing what they are doing. The short-range forces which
they master completely saturate their capability for forming and perceiving longrange
connections.
One is reminded of the analysis C. P. Snow offered in his provocative book
Science and Governnieiit for the reason why some scientists so single-mindedly
stuck to a narrow decision or were satisfied with a narrow range of investigations.
It was their success in one particular field or with the operation of one particular
apparatus. Snow dubs these men ‘gadgeteers’.
I shall assume that one does not have to defend further the proposition of the
central position of science in culture either from the radical scientism of the left
or the culture snobbism of the right. On this middle ground we shall thus posit
that the much-discussed cleavages of knowledge are all too often the unhappy
results of erroneous definition. The controversy between T. S. Eliot and his
critics, or between Snow and Leavis more recently, serve to remind us how necessary
it is for each age to rethink what ‘culture’ is in each of its multiple senses,
33 Gerald Holton

what makes the culture of a people cohere, and what forces and mechanisms are
at work to change it. In this light the important topic is not to what extent science
is separated from other activities, but rather how we may define and transmit
culture in such a way that the sciences are seen to be valid components of our
culture. We therefore must here adopt, as one of our main tasks, the actual
design of educational curricula stressing the coherence of <strong>physics</strong> with the other
components of intellectual life.
1.5.1 Threats to coherence
One of the threats to coherence is the speed with which the simplest terminology
of the contemporary sciences is being removed from the natural language of the
beginner. This makes obvious difficulties for the new learner, not to speak of the
difficulty this student wil have ten or twenty years after he has passed through
our classroom in facing, at the height of his career and ability, a science that is by
then concerned with entirely changed problems, phrased in an entirely changed
vocabulary. As we all know very well, this is also for his teachers a major and
continuing problem. But on an even more fundamental level there is the additional
and obverse problem of the effect of the increasing vocabulary gap, not
merely on the new learner, but on the language of science itself.
Margaret Mead (1 959) commented perceptively that we must find new educational
and communication devices to ‘protect society and all the intellectual disciplines
within it from the schismatic efforts of too great a separation of thought
patterns, language, and interest between the specialized practitioners of a scientific
or humane discipline and those who are laymen in each particular field’.
This is an important warning and a reason for insisting that the young should
receive early and full opportunity to learn the concepts and theories of modern
science, and so to be brought to a state where the vocabulary and grammar of
modern sciences, including some of the techniques of calculation, wil no longer
themselves be the main obstacle to an understanding of the proud achievements
of our time.
We turn to the second threat to the achievement of coherence. For the failure
of the layman to understand what the creative scientist now knows and does has
had some debilitating and even tragic consequences, particularly to the effectiveness
and morale of our most valuable intellectuals outside science. They are
caught between their irrepressible desire really to understand this universe, and,
on the other side, their clearly recognized inability to make any sense out of the
simplest vocabulary of modem science. We come to the chilling realization that
our intellectuals, for the first time in history, are losing their hold on understanding
the world. The non-scientist realizes that the old common-sense foundations
of thought about the world of nature have become obsolete during the last two
generations. The ground is trembling under his feet; the simple interpretations of
solidity, permanence and reality have been washed away, and he is plunged into
the nightmarish ocean of four-dimensional continua, probability amplitudes,
indeterminacies and so forth. He knows only two things about the basic concep-
34 Why Teach Physics?

tions of modern science: that he does not understand them and that he is now so
far separated from them that he wil never find out what they mean.
To take a concrete case consider the widely read book The Sleepwalkers by
Arthur Koestler. In it, Koestler tries to trace the rise of modern <strong>physics</strong>, and with
it of modern philosophical conceptions, stemming from the work of Kepler,
Galileo, Newton and some of their contemporaries. This is indeed still a useful
task to set oneself. Koestler has worked with devotion on his material. And, most
important, he is of course the intelligent layman par excellence whom any
scientist would be pleased and proud to have as his pupil in this evidently earnest
search for an understanding of modern science.
And yet something terrifying happened as Koestler came to the end of his
book. He had still been able to see meaning and order in the <strong>physics</strong> of the seventeenth
century; but when he turned in the epilogue to modern <strong>physics</strong>, all sense
of understanding and coherence disappeared and the incomprehensible modern
conceptions seemed to rise around him on every side as threats to his sanity.
As he summarizes his work he finds that to a large degree ‘the story outlined in
this book wil be recognized as a story of the splitting-off, and subsequent isolated
development, of various branches of knowledge and endeavour ~ sky-geometry,
terrestrial <strong>physics</strong>, Platonic and scholastic theology - each leading to rigid orthodoxies,
one-sided specializations. collective obsessions, whose mutual incompatibility
was reflected in the symptoms of double-think and “controlled
schizophrenia ”.’
I believe it is important to consider this case as sympathetically as we can; to
listen to the anguish of an intelligent man who has discovered that he cannot cope
with the modern conceptions of physical reality. For what he is saying to us is
what most people would say, if they were eloquent enough and interested enough
in knowledge to be deeply disturbed by a state of unchangeable ignorance :
Each of the ‘ultimate’ and ‘irreducible’ primary qualitiesof the world of <strong>physics</strong> proved in
its turn to be an illusion. The hard atoms of matter went up in fireworks; the concepts of
substance, force, of effects determined by causes, and ultimately the very framework of
space and time, turned out to be as illusory as the ‘tastes, odours and colours’ which
Galileo had treated so contemptuously. Each advance in physical theory, with its rich
technological harvest. was bought by a loss of intelligibility.. . .
Compared to the modern physicist’s picture of the world, the Ptolemaic universe of
epicycles and crystal spheres was a model of sanity. The chair on which I sit seems a hard
fact. but I know that I sit on a nearly perfect vacuum. .. . A room with a few specks of dust
floating in the air is overcrowded compared to the emptiness which I call a chair and on
which my fundaments rest. . . ,
The list of these paradoxa could be continued indefinitely; in fact the new quantum
mechanics consists of nothing but paradoxa, for it has become an accepted truism among
physicists that the subatomic structure of any object, including the chair I sit on, cannot be
fitted into a framework of space and time. Words like ‘substance’ or ‘matter’ have become
void of meaning, or invested with simultaneous contradictory meanings. .. .
These waves, then, on which 1 sit, through a nonmedium in multi-dimensional nonspace.
are the ultimate answer modern <strong>physics</strong> has to offer to man’s question after the nature of
reality.
35 Gerald Holton

I cannot but hear the cry of a drowning man, a cry for help that cannot leave
one unconcerned if one believes that <strong>physics</strong> can and must be shown to play a
valid, creative part within our culture. This was the end of Koestler’s road that
started with great hope and promise. What shall we do about it?
1.5.2
Promotion of coherence
One of the areas of study that would alleviate the difficulties and promote the
sense of coherence is the study of modern <strong>physics</strong> itself. The arguments above call
for substantial attention to it in the <strong>school</strong> and college curriculum.
I have little use for the attitude that one hears occasionally to the effect that
quantum <strong>physics</strong> and relativity should precede or even take the place of classical
<strong>physics</strong> in introductory courses; I believe that this is pedagogically unsound for
most students, that we must help their intuitions to bridge the distance from their
natural Aristotelian bent to the strange new conceptions by means of classical
(Galilean-Newtonian-Maxwellian) ideas. The growth of imagination recapitulates
the growth of a field to a large extent.
But whether we all agree on this or not, the main point should be beyond dispute
here. The student should, as part of his general education, arrive at an
understanding of the main concepts and theories of modem <strong>physics</strong>. This includes
certainly an introduction to quantum theory and relativity theory. Such a
programme necessitates careful consideration and use of the whole curriculum,
from secondary <strong>school</strong> to college, in order to provide enough sophistication and
tools, both in mathematics and in physical science, to ensure that the minimum
endpoint achievement in <strong>physics</strong> be not superficial. Nevertheless, this effort can,
I feel, no longer be shirked. In our world the essential notions of quantum <strong>physics</strong>
and relativity are no longer optional for anyone who wishes to regard himself as
generally educated, any more than are the essential notions of certain specifiable
other fields (for example, a biological science, an analytical social science, a historically
orientated ,social study, a literary humanistic field and a creative arts
field - to indicate by only one phrase each of the other main subjects in which a
sound general-education experience seems now essential).
But if we succeed in presenting fairly sophisticated <strong>physics</strong> to students who
will not go further in the sciences, but have done nothing more, we shall have
failed. For these students by and large do not come to us as we ourselves came to
the study of <strong>physics</strong>. We, who are trained as physicists, demanded no more than
good <strong>physics</strong> from our introductory courses. They, however, who do not intend
to become us (sometimes a difficult point to remember!), want to see also what
place <strong>physics</strong> has in the total reality, in the context of all intellectual endeavours ;
unless we help them nobody will.
It is useful first to think of the <strong>physics</strong> course that is traditionally given in terms
of a convenient model. The coverage to be attempted in a <strong>physics</strong> course is represented
on a three-dimensional ‘map’. O n the x-axis lie the academic fields that
make up the total academic educational experience of the pupil, arbitrarily
arranged from the most quantitative (mathematics) to the least (humanities).
36 Why Teach Physics7

The y-axis may represent time from say 1600 to today, which for introductory
<strong>physics</strong> courses corresponds very roughly to the development of the usual subdivisions
(mechanics to nuclear <strong>physics</strong>). The z-axis represents depths of penetration
attempted in the course on a given topic. On this map the <strong>physics</strong> course
usually given today may be represented roughly by a set of closely spaced and
sometimes overlapping pyramids, based in a more or less narrow and welldefined
strip in the xy-plane.
’600
mathematics engineering chemistry psychology history literaturem
I
today
YV
Figure 1
I
Traditional presentation of introductory <strong>physics</strong>
I
This narrow-focus scheme may be defended in courses directed to professional
physicists, but not for ‘the others’. When a <strong>physics</strong> student goes on to higherlevel
science courses, and finally to research, he eventually sees that the field he is
studying does hang together. As his study of <strong>physics</strong> penetrates further along the
z-axis of depth, he unavoidably finds that the separate ‘pyramids’ representing
mechanics, optics, etc. are ultimately joined together in a single interrelated corpus
of knowledge that stretches far to the right and left of the narrow strip under
‘ <strong>physics</strong> ’.
Although as an undergraduate <strong>physics</strong> student he wil have taken mathematics,
engineering and chemistry courses in different departments and buildings,
as soon as he tries to do any significant piece of research he discovers that
the separation between neighbouring sciences was a pedagogical, administrative
convenience, which from the point of view of living science is just as artificial as
the separation between the ‘pyramids’ in Figure 1.
Thus we find of course that an experimental research project on, say, the
dependence of molecular relaxation effects on pressure involves, sooner or later,
material from every separate block in a <strong>physics</strong> course but also brings in mathematical
methods, metallurgy, electronic engineering, chemical thermodynamics
(not to speak of the areas of politics and psychology which anyone who wishes
to obtain and correctly administer research grants in a busy department must
cope with).
37 Gerald Holton

No one who has engaged in actual scientific work can fail to have seen the
intimate connection between <strong>physics</strong> and advances in other sciences and engineering,
or between the advance made in pure <strong>physics</strong> and its social and other
practical consequences. Indeed, pure <strong>physics</strong> is an invention that exists only in
the old-fashioned classroom. As soon as a real problem in <strong>physics</strong> or any other
field is grasped, it appears that there hang from it connections to a number of
expected and unexpected problems in fields that by habit we make our students
think of as ‘belonging’ to other professions.
While the professional students discover sooner or later the existence of these
connections, those involved with <strong>physics</strong> as part of their general education do not
have this opportunity. In order to do justice to our science, to their needs and to
the commitment to a coherent conception of culture, which I have urged us to
make, we must stress with care these connections in their <strong>physics</strong> courses. In
addition to the sound presentation of <strong>physics</strong> itself we should inject into the
courses results from certain joint areas. I urge that the representation of a specific
topic, for example Newtonian mechanics, be changed from a ‘pyramid’ to a
‘ constellation ’ of related topics, roughly shown for the xy-plane in Figure 2.
f’
today
Vt
Figure 2 Connective presentation of <strong>physics</strong>
I would like to call this a connective approach tothe teaching of <strong>physics</strong>, for it
is a way of showing some of the interrelated complex of connections existing
between any one specific field of study in <strong>physics</strong> (for example, Newtonian
mechanics, or thermodynamics, or electromagnetic radiation, or special relativity
theory, or nuclear <strong>physics</strong>) on the one hand, and other fields of study (for
example, mathematics, history, philosophy, literature) on the other. The block on
relativity would be an excellent opportunity to show connections with philososophy;
for other main blocks one could develop the relation of <strong>physics</strong> to engineering,
or the relationship between science and policy making, or examples of the
use of <strong>physics</strong> in chemistry, biology and so forth.
If the central point were Newtonian mechanics, we could immediately think of
links to the past (for example, the mathematics of the Greeks) or to our present
38 Why Teach Physics?

(satellite orbits, particle scattering); to the philosophy of the neo-Platonists
before Newton and that of the Deists after him; to his effect on the atomic model
in Dalton's chemistry; to his influence on literature (the reaction against the
Newtonian synthesis by Blake and Wordsworth); to Newton's influence on economics,
on political. social and legal theory (theories of causality in eighteenthcentury
economics). Even if only a few references and illustrations are used, as
we begin to re-orientate our general education in <strong>physics</strong> there emerges before
the eyes of the pupil first the intimation, and later the proof, of <strong>physics</strong> as a member
of a constellation of concerns, so different from the usual, artificial picture of
<strong>physics</strong> as the isolated and stern subject that has nothing to contribute to anything
but more <strong>physics</strong>. Such a system would bring into the <strong>physics</strong> course a
stronger human connection without losing the scientific values and scientific
vigour.
If this view of the function of <strong>physics</strong> instruction can be made generally workable
- and in the Harvard Project Physics course. described elsewhere in this
volume, we have tried to do just that - then a response will have been made to the
warning of Margaret Mead about keeping advanced vocabulary and students in
mutual contact, and also to the disguised plea of Koestler not to condemn bright
men and women to permanent ignorance of the multifaced reality seen by modern
science. If successful we shall certainly have produced more than a mere educational
improvement. For a curriculum which stresses the connective elements
wil quite probably be copied from <strong>physics</strong> (as the successes of <strong>physics</strong> only too
often are). This would permit a truly exciting new view of education, in which
each student, in addition to penetration in depth of his own chosen field of
specialization, wil see the rest of the field of knowledge criss-crossed by connective
links, with the same major elements appearing as members of different
constellations. Thus, even as the connective <strong>physics</strong> course, when centering on
Newton's work, also explores the link to Voltaire and Alexander Pope, so should
the philosophy or literature course, when centering on Voltaire or Pope, be
exploring the link to Newton from its own vantage point.
Some of this is of course already done, but by and large each department of
learning presents its course now in an isolated, strip-like fashion, analogous to
Figure 1, the unfortunate result of too early and too single-minded specialization.
When many fields follow our lead and adopt the method sketched in the discussion
of Figure 2 our culture wil be seen. by teachers as well as students, to
have the coherences which indeed already exist, but which so far have not been
nurtured, conveyed and championed enough in our time. Letus begin here.
39 Gerald Holton

Part Two
Conditions for Learning

2 Basic Conditions:
The Nature of Learning
This edited chapter is based on papers by Jerome S. Bruner of the Center for Cognitive
Studies. Harvard University. which were presented at the Rehovot Conference on Science
and Education in Developing States. August 1969.
In this chapter Professor Bruner looks at the questions which are raised in trying to
teach <strong>physics</strong> in the context of a broader point of view concerning the nature of learning
in childhood. He deals with a set of problems that spring from the nature of the task of
trying to introduce educational technique, particularly as it relates to the teaching of
science. The issues raised are obviously of fundamental importance to anyone
concerned with science-curriculum reform.
2.1.. Why is science teaching difficult?
It seems to be difficult to teach science to a child who comes from a highly traditional
cultural background, tribal, medieval or whatever the term, but one that
we would speak of as not typical of an advanced technological society. When a
child from such a background gets to <strong>school</strong> he does not think easily in the ways
of science. Why is it so difficult? Is it not the case that science is a great open
technique of thought, one that ought to be easily adopted by anybody, since it
presents a technique for asking questions in a fashion that might be described as
frangible, breakable? One learns the art of putting questions in a fashion such
that one can easily demonstrate whether there is or is not an answer and whether
a given answer is true or not. Why is scientific thinking difficult for a young
student whatever his background ?
Whereas children of more technical societies come to the <strong>school</strong> task of
learning scientific thinking after an enormous amount of prior training in the
family, it is difficult for the children in developing societies with tribal backgrounds
who have had no such preparation. It might be worthwhile to look
therefore at some facets of the pre-training that make access into science and
scientific thinking easier for children who grow up in more technologically
orientated societies that may not be present in societies of a more traditional or
tribal nature.
43 Why is Science <strong>Teaching</strong> Difficult?

2.1.1 Language
The first of these facets has to do with certain aspects of the use of language. Man
has the capacity to receive and to translate knowledge in a linguistic form. This
permits man to convert knowledge into a form that renders it highly transformable.
Language not only permits an enormous condensation of knowledge, but
permits us to turn the knowledge into hypothetical forms so that we may consider
alternatives without having to act them out in the form of trial and error.
The possession of the gift of language also provides a way of transmitting some
knowledge without direct encounter with nature. Thus society and culture serve
to provide a buffer between man and nature as well as a storehouse of techniques
for coping with contingencies created by nature, techniques to be learned in
advance of encounter.
The hypothetical mode in language is a very simple thing if you are used to it;
if you say, for example, ‘I have nothing in my hand now, but what might I have
had in my hand if somebody had come along a moment ago with several things
and I had taken some of them?’ This is standard chatter when one thinks about
the scientific domain, but it is not the form of language that comes easily to children.
The hypothetical mode, interestingly enough, is a mode that requires dealing
with objects that are not present, dealing with objects that are not caught up in
the matrix of action.
There are studies that indicate how extraordinarily difficult it is for some
children to understand language couched in this mode as a function of the kind of
background they come from. Parents, for example, from middle-class intellectual
homes within our society wil turn out to have taught their own children this kind
of talk readily and without what seems to be any conscious effort on their part.
When you look at the language that takes place in interaction between middleclass
parents and children, you discover that there are lots of opportunities of
this kind coming up in the course of day-to-day conversation. On the other hand
children who come from homes that we now speak of in a rather empty-headed
way as culturally deprived (a term which I definitely do not like because it sounds
as if certain problems can be handled by some dosage of a special vitamin called
culture) seem not to handle this very well.
These studies indicate some of the things that one can do to teach the child to
use language in the hypothetical mode. I would choose just one example : some
preliminary work done by Dina Feitelson in Israel shows that ifyou take children,
in this particular case Kurdish Jewish immigrant children, who have not used
this mode of discourse, and play games with them where the game itself is organized
around the hypothetical mode (a guessing game or a checkers game),
you will see very striking effects of an increase in their capacity for hypothetical
discourse. It is something we take for granted, and I am rapidly coming to the
conclusion that it is the training of children in this kind of discourse that you wil
find taken for granted in formal Western technical education. Thus those who
operate in developing cultures, where the children are from tribal backgrounds,
44 Basic Conditions: The Nature of Learning

wil not find, generally speaking, in the formal curricula from the West as much
account taken of this as wil be necessary for children in developing societies.
2.1.2 Hzitnan skill and the niatiipzilntion of objects
The second major characteristic of human learning is the openness of human
skill. There is such a flexibility about how we learn things. Learning to do things
one way we seem to be able to do them almost automatically in a wide variety of
ways. Thus we develop the ability not only to use our inherited limbs, senses,
muscles and reason, but also to amplify and assist them with tools.
There is an interesting phenomenon that has to do with the manipulation of
objects that have mechanical and geometrical constraints, as exemplified in
blocks that fit together, gears that fit together. screwdrivers that fit into slots with
certain orientations, and so forth.
In the West we take it for granted that most children play a fair amount with
toys that have a built-in constraint. Children in tribal villages, however, do not
usually get an equal opportunity to practise with objects having mechanical and
geometrical constraints. It may very well be that one of the most important things
we could do is to develop - if I can use what at first seems to be an incongruous
term ~ a decent technology of toys. I would argue, for example, that the manufacture
of toys for children, not only in developing nations but in the West too, is at
the present time one of the most wasteful, thoughtless enterprises you could think
of. There are everywhere pretty cosmetic toys that have the function of tranquillizing
parents rather than aiding the children. Instead I would go about the task
of finding forms that fit together; some steps have already been taken in this
direction by various projects.
2.1.3 Learning to learn
There is a third characteristic of human learning. Not only does man learn specific
things, be they facts or abstractions, he also seems to learn how to learn. He
learns strategies for eliminating errors faster; he learns to organize information ;
he learns to anticipate; he learns to compensate for poor conditions and to
exploit good ones.
This learning to learn is compounded of many things that constitute the socalled
hidden curriculum provided by the home, the neighbourhood and the immediate
surrounding culture. It involves attitudes and values as well as strategies
of learning and thinking. To begin with there are inculcated early on some deep
attitudes about the use of mind; is it for thinking things through on one’s own
or is it to register upon and store the authoritative word handed down? Does it
carry with it a sense of hope about the possibility of solving problems or does it
portray nature and man as subject to fate, caprice and fortuity?
Not only has the child from a less technical cultural background failed to
master the elementary skills, he has also failed to develop the means for linking
himself with the powerful amplifiers provided by human culture; ways of using
45 Why is Science <strong>Teaching</strong> Difficult?

language to help one think, of using forms of logic and mathematics to help one
find deeper order in surface confusion, and forms of myth and characterization
to help one penetrate the nature of the society in which one lives. There is a
popular, if obscure, phrase among pedagogical theorists : learning readiness. It
used to be thought that such <strong>school</strong> readiness was principally a function of
maturation of the nervous system, and indeed there are some important maturational
milestones. But a good part of readiness is made up by the child’s history
interacting with his maturing capacities.
To cite a specific example. Mischel has shown in a series of brilliant investigations
that the child of a slum or of a depressed area undergoing rapid and disruptive
social change, such as in urbanized West Indian islands, wil not forgo a
small reward now for a bigger reward later. In consequence he wil persevere less
at problem solving, try out fewer solutions, take less time for the sake of mastery.
2.1.4 Expanded code of language
There is another thing that Basil Bernstein and others have called ‘the expanded
code of language’. It is extremely important for <strong>school</strong> children to grasp the way
of using language in a more expanded form in which they can talk about things,
bring up associations, identify an object in its connotations.
This is particularly significant for a child using a second language for his
<strong>school</strong> work. Working in Senegal a few years ago Dr Greenfield of our laboratory
tried an informal little experiment in which she got children to play guessing
games in French and in Wolof, and it was touching- the richness ofthe guesses in
Wolof and their poverty in French. Not that the French language is not rich in its
capacity, but for the Wolof child it was lacking in its web of associations and
fantasies. A language that you have never been happy in, never been angry in,
never made love in, a language that is only for <strong>school</strong>, is no language in which to
develop the enterprises of the mind.
I am fully aware of the necessity for mastering languages to give access to the
techniques and culture of other people; this is clearly true. But I would like to
urge that instead of using the stiff instrument of a new language in which one has
felt nothing deeply, but only talked about cold subjects, we should arrange for
such instruction to be in the native language to allow for the development of
what are spoken of as cognitive structures.
There is one more very important technical argument that has to be introduced
here. It turns out that there is a constraint on human thought processes, perception
and so on, that is jokingly called in the trade ‘the magic number seven plus
or minus two’. The magic number seven plus or minus two refers to the fact that
the human mind - and indeed, any nervous system for that matter ~ is not
capable of dealing with a large range of independent events at once. It is usually
thought that we can keep track of about seven streams not correlated with each
other. The moment you force the individual to make decisions of a highly conscious
type, with respect to the choice of words and the construction of sentences in
another language, you are using up some of that magic number seven plus or
46 Basic Conditions: The Nature of Learning

minus two. and there is less left for the information processing that is required
for dealing with the substantive nature of the material at hand. So I plead with
you. although I know that there are tremendous political and ideological overtones
to the use of native languages for entering into complicated intellectual
material, give it one more chance. while carrying out the second-language
instruction that goes along parallel with it.
2.1.5 The problem in developing countries
I could go on to other kinds of things, for example the problem of learning certain
kinds of basic concepts that have to do with the notion of necessity as opposed to
that of probability: that something is necessarily so as compared to just highly
likely so. There is a whole range of similarly basic concepts that come up spontaneously
in the conversation of people who live in a culture that is. in a sense,
deeply and pervasively structured by the science of generations and by the technology
that shapes the mind.
I would like to argue, and I think I can make a very good case for it, that there
is a kind of impedance match between the thought processes and the technical
things within a culture which forces people in technical societies to a way of
thought that is quite different from those whose cultural background is different.
But let me end this section by pointing out that if developing countries expect to
get much help from Western <strong>school</strong> systems which include the inculcation of the
type of non-specific skill that is necessary and is presupposed by scientific
thinking they are bound to be disappointed. For our part I would like to look to
developing countries for some aid in understanding these matters, so that we can
then incorporate some of this ourselves with our own children, because we have
been too neglectful of this.
The West is not going to be able to help developing countries very much in this
way because we have not understood these things very well; and in any case in
the West they mostly take place outside <strong>school</strong>. I strongly urge developing
countries also to think about things outside of <strong>school</strong> and not to assume, as too
many of us have, that education takes place within those narrow four walls
called a <strong>school</strong> and there only.
2.2 <strong>Teaching</strong> about science or scientific theory
What do we mean when we say we are going to try to teach a pupil about science
or scientific theory? I think it can be argued that a theory, or a scientific theory, is
a canny way of thinking about a great many things while keeping very little in
mind. Basically what we do when we build a theory is to reduce it to a minimum
set of propositions or ideas, from which we can then generate lots of specific ones.
I think that the development of theory is a response to the limited capacity of
mind to process information. What we do when we build ‘theories in the mind’
is basically to set up some kind of a model of the event, a model that we carry in
our head: it is a model that permits us to go beyond the information that we have
47 <strong>Teaching</strong> About Science or Scientific Theory

een given; it allows us to extrapolate, to interpolate; it allows us to do all sorts of
things that are predictive.
The model is valuable in the sense that you never go directly, so to speak, from
having no theory to having a theory. It is always the case, with respect to any
range of phenomena, that when you face a child with a lesson you discover that
he already has a way of thinking about the range of phenomena that you propose
to teach him about. The task that you have is not so much giving him something
afresh as a gift from the gods but rather replacing what he has. And one of the
great rules of pedagogy, and indeed of criticism, is to start where your listener is,
to start from his present presuppositions. In this sense it is indeed not true that
Newton’s laws are the same in every culture and every place, because Newton’s
laws in one case fit one context that has preceded them and in another case they
fit another, and perhaps not as well.
I would like to bring up a general question. Is it not the case that in order to
teach children in <strong>school</strong> there is a prior step, that I will speak of as pedagogical
anthropology, of finding out what in fact are the theories, the models, that these
children have in mind initially? Everyone who has worked on curriculum projects
~ in middle-class suburbs, in inner cities, in Asia, Africa, Latin America or
wherever ~ has had to start from the position that there are points of view that
exist prior to starting, and that it is necessary somehow to take these into account
in order to cut down confusion and noise.
Granted that this is the case, we can now go on to say something fairly specific
about the proper sequence by which one takes the child from where he is into a
subject matter. Let me illustrate with one piece of curriculum construction in
order to give you an introduction to what strikes me as a very central issue in
studying the possible sequence by which an idea or a set of ideas can be got
across.
It had to do with the problem of teaching some problems in conservation. It
was in a large auditorium. Phillip Morrison, Frank Oppenheimer and I were
working with children eight or nine years old; we were interested in the way in
which they might understand certain kinds of problems in classical mechanics.
What we did was to attach to the ceiling some nylon threads, and attach to the
nylon threads some croquet balls of uniform size and weight with a marked tape
stretched horizontally beneath them. We started with one ball and took it to one
side, to a position over number six on the tape (zero was in the middle), and
asked the children how far they thought the ball would swing past the middle to
the other side. The first group of children predicted the ball would swing to
three on the other side. We asked thenwhy they thought so and they said, ‘Well,
here it is going downhill and here it goes uphill.’ This was perfectly obvious and
we agreed that it was perfectly obvious. We let it go from six. Fortunately the air
was not all that dense, and the ball went right up to six on the other side. Like
good human beings the children’s first response was disbelief. They said, ‘Let us
do it again’, to see whether there was something special about the result. We
took it up there again to six, dropped it, and it went to six again. They did it a
48 Basic Conditions: The Nature of Learning

third time, and it went to six three times in a row, and then it became highly
probable for them.
So we said, ‘All right. Now that you understand. we want to do another little
experiment.’ We now had two balls hanging. ‘We’re going to take one out to six,
leaving this second one hanging in the centre. The first is going to collide with
this second one. How far wil the hit ball go out?’ They said, ‘Oh, let’s see. If you
take it to six here. perhaps two.’ And we asked, ‘Why two?’ and they replied,
‘Well, you see, it is coming down here free and then it has to push.’ Please note
there is a very good theory here. It is the ‘body-kinetics theory’; essentially you
have got to push or exert energy. We dropped it and it hit the second one; that
went majestically up to six, as it should. Again they wanted to do it three times
and were duly impressed, very impressed indeed. Now we did the same thing with
a set of four of them, taking one out and leaving three sitting behind. The usual
happened. The children were delighted and dumbfounded. How could this be ?
W e let the children play awhile. When we came back, they were doing things
like taking two of them up to six and dropping them. and two would sail off the
other side and go to the right numbers. One of the children acted surprised at this
result and another said to him, ‘What are you surprised about? There are two of
them with six-worth of movement in them. It’s got to go somewhere.’ That was
the pay-off.
I want to urge that this is deep understanding. Et is an intuitive non-quantitative
understanding, but it is a deep understanding of a phenomenon. Let me come to
the formal way of saying this. I think generally speaking we can distinguish three
ways in which we know something.
The first way of knowing is in terms of a skill, of knowing how to do something.
It is the way, for example, in which a child knows how to move a see-saw
up and down before he can tell you anything that begins to approach the law of
moments. before he really knows anything of a fulcrum or anything else. It is a
way of doing something; it is the way in which a child knows all kinds of things,
like riding a bicycle or playing certain kinds of sports.
There is a second way of knowing that has to do with the problem of being able
to put matters into imagery ~ having an image of it, having a picture of it - not a
picture that is a copy, because there is nothing to copy. Indeed, the thing that is so
fascinating about good intuitive imagery is that it has a selective, generative
property, a way of representing something that is not a sample of it and is not a
faint copy of it. And it is an extremely interesting thing to equip children with
good imagery, a phenomenon which is something we do not fully understand.
There is a third way of knowing that has to do with translating what is known
into a language. In effect it is what we do in taking what we have observed and
imaged and converting it into language, into sentences in such a way that we no
longer need to manipulate the objects themselves but can manipulate the world
by manipulating the language that stands for it. This powerful technique does
not just involve a natural language but is, of course, the stuff of mathematical
notation as well.So that you could argue. as indeed many people have argued,
49 <strong>Teaching</strong> About Science or Scientific Theory

that whatever can be said in mathematics can also be said in ordinary language,
except that it takes an awfully long time to say it and it does not condense as
readily. But in general there is this third way of representation of the world,
through language.
One of the most interesting things that one does in learning something is to
take these three forms of representation, in the mode of doing, the mode of
imaging and the mode of language, and relate them to each other: This is what
discussion is about; this is what laboratory exercises are about; this is what diagramming
is about. And I rather suspect, as I have seen most new curricula
develop, that we have not yet paid sufficient heed to the importance of translating
from one medium into the other.
I would like to urge that if one has no better theory as to how to proceed in
teaching, one should begin with some mode whereby somebody does something,
then go on to form a guiding image of what one has done and finally put it into
words; and work with these three media together, recognizing the fact that skilled
manipulation of materials may be easier than being able to image those materials,
which in turn may be a little bit easier at the start than being able to describe them
in a uniquely good way.
2.3 When do we start teaching?
When do we start teaching a child different things? When do we really begin the
process of educating a child in science? It was less than a decade ago that I
received a letter from Mr Conant, formerly President of Harvard, in which he
raised serious questions as to whether it might not be just a waste of time to
try to teach children in elementary <strong>school</strong> anything about science, since science,
as he put it, was so dependent upon mathematics. It was about a year ago that we
happened to be sitting next to each other at a dinner in New York when he
laughingly reminded me of this letter that he had written ten years earlier, arguing
that his changed mind was a demonstration of the fact that people over seventy
could still go on learning!
It is quite plain that we have to start science at an early age. I got into trouble a
few years ago by making the remark that any child at any age could learn any
subject in some form that was honest; and indeed I would even go on to add,
with some satisfaction, that I have yet to run into a negative instance. But the
statement needs some clarification. First of all I mean that any subject you
choose, any subject in science, because that is our main concern, has about it
certain kinds of non-specific skills, of the kind that we have been talking about,
that one has to learn, certain kinds of language usage, ability to create images, to
entertain hypotheses, to think in terms of cause-and-effect and so on. That is one
sense in which it is necessary to start teaching the underlying presuppositions as
early as possible.
There is a second sense, however, and it has to do more with the business of
taking the subject matter that you are going to teach and beginning it in some
mode of presentation that is essentially manipulative, and in building from there
50 Basic Conditions: The Nature of Learning

on to some worthwhile working intuitive imagery, for example what we have
done a lot of in mathematics. With the ball experiment, going from manipulation
to imaging was terribly important, and it is of course a major feature of much of
what we are doing in our curriculum projects.
It may mean that we have to get a child ready much earlier than before, and
also to do this in cultures where there is not the preliminary conditioning that
can take place within the bosom of the family. IfI had a message over and beyond
the message of starting early and giving the child more mastery in language, it
would be that you have got somehow to consider what happens before the child
gets to <strong>school</strong>. Ifyou wait until the child gets to <strong>school</strong> you run the risk of creating
a failure situation in which the child feels that something is out of reach. This has
happened so often now that I know it needs no repeating.
2.4 Creating optimum situations for learning
First we must be concerned with the pupil’s growing conception or representation
of the world around him. In preparing materials to aid the child’s learning the
curriculum must fit into the child’s available modes of knowing, his representations.
At the outset the child’s approach to the world is in terms of action and the
development and realization of sensory-motor skill. He knows by knowing how
to and his knowledge expresses itself in the organization and guidance of action.
In time, and gradually, this form of learning is supplemented by a capacity to
summarize events and actions in the coin of imagery. There is a concreteness and
perception-bound quality in the child’s intelligence during the years, say, between
three and seven that contrasts vividly with the deeper-lying, vivid fantasies
that also characterize the child. Knowledge at this stage is spotty, ragged and
fractional, and tends to deal with very few features of things at any one time.
Eventually thought and problem-solving come to embrace concepts, to deal with
more logical operations, with possibilities taken in combination rather than with
events taken singly and in fragments. The details are complex and the controversies
that exist about these matters real, but the general outline is reasonably plain.
By the time the child is well into <strong>school</strong> he is capable of knowing things through
action, through image and through symbolic-linguistic representation.
What is required, as the child progresses, is opportunity to exercise his growing
and maturing capacities - not to ‘speed him up’ through the course of development
but to give him easy control over, and confidence in, his abilities to cope.
Where these are not so mastered, and where confidence fails to develop, we have
the child who defends himself from the threat of failure inherent in learning. It is
when this happens that we encounter the learning block, the <strong>school</strong> phobia, the
chronic under-achiever. It would seem, moreover, that the growth of learning is
organized much like a set of prerequisites, where the mastery of one skill or one
conception either frees the child to move on to a next one (that is, provides a set of
components that wil be organized as a subsequent skill matures) or provides the
meaps by which the child comes to comprehend a new relationship.
51 Creating Optimum Situations for Learning

In general, learning itself is its own reward as it moves through a cycle of skill
growth and consolidation. And much of learning in natural, apprentice-like
situations has this property of intrinsic reward. Various writers in the past
decade have postulated what has come to be called ‘effectence motives ’ that impel
the organism toward mastery and satisfaction of curiosity for its own sake. I do
not know whether much is served by postulating such a drive, but that satisfaction
is gained from such effectence achievement is beyond question.
Why then do we need other forms of extrinsic reward? Let me make plain that
extrinsic rewards - be it in the form of praise, grades, prizes, or whatnot ~ have
little direct effect on what one learns save in highly restricted situations. What is
crucial to learning is knowledge of results and the possibility of using error for
correction. That is a matter of information rather than of commerce in prizes or
approbation. Mastering an equation, a sentence in a foreign tongue or a bodily
skill depends only indirectly upon the prize one gets after the episode is over.
Extrinsic reward rather directs attention and sustains it, and above all else indicates
that what you have learned matters to somebody else, notably to the
society of which one is a member.
What is crucial about intrinsically motivated learning is that it must be buttressed
by knowledge of results as it goes along. knowledge which <strong>school</strong>s, for example,
often do not provide. But intrinsically motivated learning can also be
supported by providing materials to be learned that are themselves capable of
leading to insights and skills that can then be channelled into deeper insights and
more powerful skills. The great disciplines of learning have precisely this structure
and that is one of the most powerful pedagogical reasons why they are
worth teaching. There are plenty of practical reasons. obviously. As you all
know, there is now a world-wide movement to reform curricula in the <strong>school</strong>s of
many countries much along these lines. One of the mottoes of this effort is that
any subject can be taught to any child, at any age, in some form that is interesting
and honest. This means basically that one can readily start a child on his or her
way with some early version of a more complex notion or skill, rendered in the
form of an exercise in manipulation or in imagery, before the idea or subject is
given in its more complex form. embodied in a highly abstract, symbolic notation.
What this guarantees, of course, is that the child can then go on to as much
depth and precision as he can master. He is then becoming deeply involved in his
culture.
In fact, <strong>school</strong>s are improving, though they are doing so neither fast enough
nor with enough regard for the child whose home background leaves him deficient
in the hidden curriculum with which we began this discussion. Experience in
many developing nations, particularly in Africa, underlines the importance of
preparing the child in the home setting for <strong>school</strong>. And indeed it is of deep importance
in these developing areas that, in the elementary <strong>school</strong>s particularly, there
should not be a slavish imitation of the European <strong>school</strong> pattern.
Our task is not so much that of adapting the Western <strong>school</strong> to new conditions
elsewhere but rather of inventing new means for relating flexible human capacities
to the challenges and requirements of developing societies. We must not
52 Basic Conditions: The Nature of Learning

limit ourselves to the <strong>school</strong> as the sole instrument of education, for it has represented
a very small part of the process of preparing human beings for the challenge
of change. It is the very conception of growth itself, and how we assist it
through the life cycle of the human being, that is now the issue. Perinatal care,
toys in the nursery, opportunity for early application of what one has learned,
the restructuring of work to match one’s age, these are as important in the broad
picture as curricula, teachers and text<strong>books</strong>.
53 Creating Optimum Situations for Learning

3 When to Teach Physics
This chapter is contributed by E. J. Wenham. Elsewhere in this volume it says that the
<strong>physics</strong> teacher who ignores the basic findings of such investigators as Piaget does so at
his peril. Unfortunately not enough work has yet been done in this field. but this chapter
draws attention to this problem which should be the concern of all those involved in
developing new programmes.
Physics, the fundamental science, has been a <strong>school</strong> subject in many countries
for a very long time. Usually it is taught to selected students, who are often selfselected
because of their reaction to its mathematical content and its extensive
use of mathematical symbolism. In such cases it is not unusual to introduce the
subject to eleven- or twelve-year olds, and it is still, at times, introduced as a
rigorous, logical discipline.
In order to consider the wisdom of this situation, one must first look at man's
knowledge of the development of logical thinking in children. Then one has
some evidence on which to base a judgement about the best way and the right
time to introduce children to the subject.
3.1 The development of the child
Research undertaken in the last two or three decades into the growth of basic
mathematical and scientific concepts (e.g. volume, area, acceleration) in children
has revealed what a slow and complex process this is and, moreover, that our
understanding of it is far from complete. But enough has been learned to show
that such concepts develop from vague, even incoherent, notions which are
slowly refined as the child matures and assimilates new experiences. This process
depends upon the abilities of the child himself, upon his desire to grasp the concept
(i.e. his motivation) and upon the environment in which he is immersed.
This view, which developed under the leadership of Piaget (Piaget and Inhelder,
1958) in Geneva, suggests that three major stages can be distinguished in
the intellectual development of the child. The first stage, which hardly concerns
the teacher of <strong>physics</strong>, ends perhaps around the age of five or six. This is the stage
when the child is learning to relate his actions with his experience, his response
being largely a trial-and-error adjustment. The child in this ' pre-operational '
stage lacks in particular an appreciation of what has been called 'the concept of
54 When to Teach Physics

eversibility'. He is unlikely, for example, to appreciate that a plastic ball may
readily be squeezed into a new shape and just as readily returned to its original
shape. Whilst he may accept that the plastic material, whether in its initial or its
final state, is permanent, he has no appreciation of the conservation of the
matter within it throughout the deformation. Lacking these concepts of ' reversibility'
and 'conservation' the child is unable to understand some of the bases of
mathematics and of the sciences.
But as he enters <strong>school</strong> he is likely to be entering upon a new major stage in his
intellectual development. This stage is one of concrete operation. At first he
elaborates the mental operations of which he is capable and then, still dealing
largely with objects which he can handle or imagine in some concrete form, he
accumulates data from his environment and begins to organize it and to select it
in his efforts to solve the problems which that environment presents to him. The
element of trial-and-erroremains but now his response is controlled by a thought
process rather than an action. He is now acquiring the concept of reversibility : he
can imagine the deformed plastic returning to its original shape, for example, or
he can observe that in an attempt to balance two weights he has put too much
material on one side of the balance and that this can be compensated merely by
going back and reducing that material again. He also acquires some understanding
of conservation ~ usually applying this to matter first and then to weight and
finally to volume. The physicist will note that the word 'conservation' as used
here has not got quite the same force as in such a phrase as 'the conservation of
mass'. Here the word implies no more than that the quantity of matter, or the
weight of that matter and indeed the volume of the matter (taken to be solid or
liquid), does not change during the child's experience of it. The relative lateness
of this development, which coincides in so many countries with the change from
primary to secondary education,, is of immediate significance to the <strong>physics</strong>
teachers. Until this concept of conservation is clear we cannot expect to teach
the concept of density (involving, one observes, the interrelation of two of these
attributes of matter - volume and mass) in a fully meaningful manner. Nor,
indeed, could we expect to deal with the measurement of volume before the child
has a feeling for its conservation.
A third stage follows at some point between the ages of ten and fourteen ~ and
for some this is a stage which may never be reached. Now the concrete operations
of the second stage become formalized. The dependence of the adolescent's
thinking on the concrete objects (whether real or imagined) of the past is now
slowly replaced by a process which involves operating in the mind with hypotheses,
considering the variables and generally thinking as a physicist thinks.
The transition to this mode of thought is evidently of the greatest importance
to the teacher of <strong>physics</strong>. Until his pupils have reached this stage of formal
operation, the teaching of formal physical and mathematical descriptions is
likely to prove ineffective. Nevertheless, it must be remembered that the provision
of suitable experiences within a favourable environment may bring this
important transition forward.
55 The Development of the Child

Here indeed is the fundamental task of the teacher at this boundary zone
between the stages; that of providing appropriate experiences which wil encourage
the child to move through the stages of intellectual development as surely
as possible. In doing this we must observe that ‘adult logic’ is not ‘child logic’.
The child does not meet the adult until he reaches the stage of formal operations.
The application of this work of Piaget and his followers to <strong>school</strong> teaching has
been very effectively undertaken by the teachers of mathematics. Its lesson for
<strong>physics</strong> teachers is equally clear.
Whatever <strong>physics</strong> is taught to children before the age of about thirteen must
provide ample experience with the materials and the phenomena of the physical
world, and such experience must be real experience with real materials. In many
developing countries there is the special problem posed by a pervading cultural
background, which may not be conducive to the development of the scientific
modes of thinking (Gay and Cole, 1967). This situation can be resolved only by
providing adequate compensation at the primary-<strong>school</strong> stage. All such provision,
whether at the primary or at the secondary stage, must be significant to the
child ; it must in fact relate to his everyday environment. Attempts to construct a
formal, logical structure should be avoided, and teachers must learn to accept
that pupils will not possess the complete concept with which they themselves are
so familiar, nor wil they be ready for its immediate application. This is not to say
that the difficult concepts of <strong>physics</strong> may not be used. There is virtue in the introduction
of such concepts even in partial form: the idea can then have time to
mature as the child matures. An example of this in action can be found in the
Nuffield Physics (1960) course for eleven- to sixteen-year-old pupils. The very
difficult concept of energy is there introduced to twelve-year-old pupils in the
sense of something which is got from fuel so enabling men to do useful jobs.
Energy transformations are considered - all with suitable experiments ~ and it is
noted that heat is often involved. It is another three years before the experimental
evidence for energy conservation is considered and the concept itself refined in
consequence. In the meantime the teacher must rest content with an informal,
limited comprehension rather than with a formal statement which may certainly
be learned by heart but which remains without significance.
3.2 Other factors
Physics is but one among the sciences. It is characterized, perhaps, by its consistent
and necessary use of mathematical symbolism. And this is a severe deterrent
to many, unless one can depend on imaginative and sympathetic mathematics
teaching.
It shares with other sciences the characteristic style of scientific investigation
and thought and it may be that elementary studies for pupils in the age range 9-1 3
(which may span the end of the stage of concrete operation described above)
should be based upon integrated science studies (CIES, 1968), provided that
these do give a proper weighting to the physical world. Such studies should include
a wide variety of first-hand experience with the phenomena which are the
56 When to Teach Physics

proper study of <strong>physics</strong>, and this in turn would be a sure foundation upon which
to build a <strong>physics</strong>-teaching scheme with older pupils. But one must remember
that as a highly structured subject <strong>physics</strong> is likely to remain a major interest for
the few rather than for the many. Early courses in the sciences have therefore a
dual function - that of providing the world with scientifically literate citizens and
of preparing for more advanced work for the few.
3.3 When to teach <strong>physics</strong>
In the light of current experience it would seem wise to teach <strong>physics</strong> as a formal
subject to children who have attained the maturity which characterizes the adult
mode of thought. This suggests that ‘pure’ <strong>physics</strong> courses (where these are
appropriate) might commence with pupils of say thirteen years. Prior to this,
adequate experience with the materials and phenomena of the physical world
should be provided for all children and special care should be taken to provide
such experience in areas where the cultural background is not conducive to the
development of the scientific approach. Such areas are to be found in all parts of
the world, and programmes in primary education must provide compensation
for any deprivation which is inherent in the immediate neighbourhood - whether
this be a city slum in an industrialized state or an up-country village in an
emergent state.
It would be good if teachers could determine with more certainty exactly when
a particular child has passed the threshold of adult thinking. But the recognition
of this need is so recent that specific tests which might be applied are not available.
Those interested in this as a general problem rather than one specific to <strong>physics</strong>
wil find assistance in the Bristol Achievement Tests (Brimer et al., 1969).
An alternative approach would be to find ways of helping teachers to identify
those children who are ready for the more formal work. Research on this is proceeding
in connection with the United Kingdom’s ‘Science 5-13 Project’.* To
help teachers to recognize those behaviours in their children which are indicative
of readiness for the formal approach. it is necessary first to identify those behaviours
and then to provide the teachers with a series of questions which they
may ask themselves about each child. Such a procedure does not differ in essence
from what a thoughtful, sensitive, well-trained teacher would do anyway, but it
should provide valuable assistance in crystallizing the technique.
* Science 5-13, With Objectioes in Mind, to be published by Macdonald.
57 When to Teach Physics

4 Problems of Language in the
<strong>Teaching</strong> of Physics
This edited chapter is based on contributions by Peter Strevens, one of which was a
paper given at the Rehovot Conference on Science and Education in Developing States,
1969, and by L. S. Kothari. The problem of language has not always been given the
attention it deserves by those drawing up new science teaching programmes. It is
particularly important in those countries where science instruction in the secondary
<strong>school</strong> is given in languages which are the second language of the pupils and not the
mother tongue.
The chapter begins by considering various linguistic and conceptual problems in
science teaching, and by discussing some of the limitations of certain languages and then
the problem as seen from a developing country. The case is put for encouraging the
teaching of science in the mother tongue, although the need for a second language is
accepted for those going to higher levels of science. The chapter concludes with a strong
plea for closer collaboration between laaguage teaching and science teaching.
4.1 Language in advanced modes of thought
It is generally agreed that the education of scientists and technologists entails the
understanding of a great many concepts and the ability to read, listen, talk and
write about them. In order to do this, and in order to teach any subject, not least a
scientific one, certain complex modes of thought have to be used. These modes of
thought require and use certain patterns of language. For example, English,
French and all the languages commonly used for advanced scientific study use
groups of words and expressions which we wil call grammatico-logical operators.
They are essential for expressing any kind of complex, abstract and especially
recursively-abstract ideas, whether scientific or not.
In English, the set of grammatico-logical operators includes at least the following
:
Type (i). although, because, if, only, therefore, once (something has occurred),
since (something has occurred), unless, until, whenever.
Type (i). as a result of, as if, as long as, for the purpose of, if. .. then. . . , in
order to, suppose. .. then. .., since. .. then. ...
Type (iii). however, nevertheless.
58 Problems of Language in the <strong>Teaching</strong> of Physics

These lists are not exhaustive but they contain most of the common words and
expressions which carry the essential logic and mental ideas of relationship,
causality, consequence, interaction, complexity and abstraction. They are vital
not only to an understanding of science but equally to complex logical thought
verbalization in any field of discourse. Mastery of these is normally confined to
those whose education reaches the secondary level, but it is essential to the learning
of <strong>physics</strong>, certainly in the higher levels of secondary education, that facility
with them should be part of the pupil’s background. He must be able to understand
these words and expressions, and to be able to use them in speech and
writing (to ‘verbalize’ them). The ability to understand and use these words and
expressions depends on maturity (younger children cannot handle the mental
processes involved), intelligence (some children never grasp the whole range of
these items) and experience (unless these ideas and expressions are included in
the child’s education, he wil meet them in everyday life only occasionally and in
a random fashion).
4.2 Generalized concepts
Science requires the understanding of many concepts and the extent and nature
of concept-formation is essential to our enquiry, especially as this may have an
important bearing on the learning of <strong>physics</strong> at the secondary level in those
countries where the language of instruction is a second language and not the
mother tongue.
The question hangs on the meaning of ‘scientific concepts’, and here we find
multiple ambiguity. The term is used both loosely and with apparent precision,
though the precision evaporates upon closer inspection. The various usages of
the term (other than the purely conversational) relate to five distinct ideas: first,
to certain linguistic skillscommon to all advanced academic or scholastic study ;
second, to certain characteristics of the habits of thought of the individual
scientist; third, to a number of concepts prerequisite to science but not unique to
it; fourth, to one special prerequisite, that of practical numeracy; and fifth, to
those concepts which are unique and proper to science, or which if they are not
unique to it are at least inseparable from it. We shall look in turn at each of these
uses of the term ‘scientific concepts’.
A set of ideas which are frequently spoken of as ‘scientific concepts’ comprises
a certain objectivity of outlook on the universe on the part of the individual,
together with an ability to generalize from observation and to perceive and
describe relationships and influences. It is customary to regard a preference for an
objective, descriptive, rational outlook or alternatively for a subjective, impressionistic,
non-rational outlook as if these attitudes were inherent to the individual
personality. This is difficult to believe, and in the absence of evidence to the
contrary intuition suggests that such preferences are learned behaviour. If that is
so, these attitudes may not be determined by intelligence and may be open to
acquisition by all individuals, although it may well be that there is a developmental
age at which they are more easily learned than at any subsequent time.
59 Generalized Concepts

Another group of notions for which the label ‘scientific concepts’ is sometimes
used includes being able to generalize deliberately from observations, to talk
abstractly about the generalizations and to discern and describe relationships,
influences and patterns. These abilities seem to relate to aspects of intelligence in
the individual as well as to a fairly late stage of mental development.
The next type of ‘scientific concepts’ is practical numeracy: the ability to
carry out a certain amount of mental arithmetic, to visualize in graphs and diagrams,
to take for granted the use of statistical statements and above all a willingness
to describe by quantifying. These abilities, like all the preceding ones, are
essential for learning science. But they also form part of the general education of
most young people whose education reaches the upper secondary level, whether
or not they later specialize in science.
All these sets of ideas are necessary for the learner of science if he is to progress
very far; they also form part of the education of specialists in other branches of
learning. So we may now refer to them as ‘ generalizing concepts ’ in contrast to
those unique or essential to science, which can more properly be described as
‘scientific concepts’. Because they are prerequisites for the education of the
scientist the generalizing concepts cannot be ignored. They must be seen to
constitute a learning problem of a conceptualizing kind for all advanced learners.
When the learning is in a second or foreign language the same question arises as
for science: is the task of concept-formation different compared with learning in
the mother tongue?
It is necessary for the teacher of science to remember that many of the pupils
who are unsuccessful in science and fail or drop out of courses do so because in
their general education they were given insufficient help in learning to understand
and verbalize the generalized concepts which the science teacher requires
and takes for granted. At the beginning of their science courses such pupils can
still be rescued; after a year or so of science it may be too late.
4.3 Scientific concepts and the languagdof science
Within the concepts unique and proper to science it is possible to recognize
large numbers of sets of concepts corresponding to different branches of science,
different stages of general scientific discourse and different specializations.
A number of examples of sets of generalizations and concepts are given below.
This list consists of non-comprehensive examples of linguistic and conceptual
devices used in science. The object of including them is to remind the reader of a
few of the very large number of concepts which we use and expect our pupils to
use at the secondary level, certainly in the higher stages.
1. Linguistic additives. (a) a-, anti-, ante-, CO-, contra-, extra-, non-, pre-, post-,
re-, sub-, etc.
(b) -ate,-ation,-ator,-able,-ible,-al,-ic,-ical,-ize,-ization, etc.
2. Some conceptual processes involved in learning science. classifying, measuring,
space-time relations, communicating, inferring, observing, quantifying, abstrac-
60 Problems of Language in the <strong>Teaching</strong> of Physics

tion-making, model-making, hypothesis-making, testing, theorizing. predicting.
replicating, extrapolating, generalizing, etc.
3. Some basic scientiJic concepts. observation, identification, differentiation, classification,
experiment, description, etc.
4. Examples of some ‘ experimental’ notions. crystallize, evaporate. volume, pressure,
flow. vacuum, electrode, hydrolysis, distillate, residue, etc.
5. Another group ofterms. force, field, flux, influence. attraction, repulsion, rotation,
spin, precession, etc.
6. Some ‘ theoretical’ concepts. evidence, support, confirm, model, standlfall,
interesting, trivial, irrelevant, important, postulate, prefer, reject, axiom, law,
principle, corollary, hypothesis. validate, valid, invalid. tenable, untenable, infer,
suppose, assume, presupposition, etc.
7. Some ‘mathematical’ concepts. alike, different, greater, less, include, exclude,
increase, decrease. reduce, member, class, unit, set, combine, separate, order,
sequence, sequential, simultaneous, precede. follow, subsequent. zero, infinite,
indefinite, random, add, subtract, take away, etc.
Every human being learns to form a great many concepts and to verbalize some
of them. Every language expresses the concepts habitually used in the society it
belongs to. In each case there is a wide range of variation. To take the individual
first, there is a great deal of variation between the degrees of recursive abstraction
which can be effectively handled, whether receptively or productively, by different
individuals. (We are considering here not just the subset of concepts referred
to above as grammatico-logical operators, but concepts in general, very many of
which are not verbalized.) One of the functions of education is (or ought to be)
to steer each individual to the limits of his capacity in developing concepts; one
of the tasks within science education is to ensure that the complexity of the
concepts being presented at each stage is not beyond the capacity of the individuals
concerned.
Scientists and science teachers often assume that it is only the technical vocabulary
which is special about the language of science. But in practice it is vocabulary
which is the easiest part of science teaching: if the scientific point of an experiment
is fully understood, the technical terms wil be easily learned.
Another difficulty can often occur for the pupil when he meets sentences that
contain everyday words used in a special sense. For example, let in ‘let the weight
of copper represent . . . ’, meaning it does represent ; conclusion in ‘state your
conclusion from this experiment ’, meaning what have you learned; or may in ‘the
tube may now be disconnected’, meaning it must be disconnected.*
* This last example is of course a misuse of language. The author of the book could as easily say ‘the
tube must be disconnected.’ Similarly the author might say ‘state what you have learned from this
experiment.’ Authors have responsibilities not to abuse language by using jargon which is clumsy and
ambiguous.
61 Scientific Concepts and the Language of Science

In short, teachers need to make sure that all pupils understand the language
which they and their text<strong>books</strong> use.
4.4 The problem of certain languages in teaching science
The test of foreign or indigenous shall not be applied to any word but only the test of
currency.
Mahatma Gandhi
As far as languages are concerned, it is important to distinguish between what is
the present position and what could be the position in the future. Very many
languages do not at the present time incorporate equivalents of the verbalizations
of scientific concepts which exist in English, French, Russian and the other
languages in which scientific study is customarily pursued. But we should avoid
falling into the error of arrogance and feeling that these languages are therefore
in some sense defective, inferior or primitive. A language reflects the culture of a
particular society. If that society includes science within its culture, the language
wil contain all the necessary concepts and devices for talking and writing about
science. If a society with no previous history of scientific interest begins to acquire
such an interest, its language ~ any language ~ can and wil develop internal grammatical
and semantic rules for doing so. (Hebrew is an example of a language in
which this process has taken place in modern times.) Unfortunately the task of
developing scientific concepts ab initio in a language takes a good many years and
can only rarely be engineered as a deliberate policy. Such development does not
constitute a practical solution to the shorter-term problems of science education.
Languages vary, then, in the extent to which they give expression to both
generalizing and scientific concepts. In saying this we are categorizing the mother
tongues of potential scientists, who have thus been brought up speaking languages
which carry all,or many, or few of the total range of concepts relevant to
education in science. What difference does this make to the education of the
individual? The answer depends not only on the extent to which generalizing and
scientific concepts are present in his mother tongue, but perhaps even more upon
his age and the extent of his education in his mother tongue before beginning to
learn science.
The young child who begins to learn science in an educational system where
English or French (for example) is the medium of instruction from the beginning
of <strong>school</strong>ing wil be relatively little affected, compared with the adult, already
literate in his mother tongue and thoroughly imbued with the culture of his own
society, whose encounter with science comes after the completion of adolescence.
The young child’s learning of concepts and his grasp of the more complex
devices of his language are still largely &fore him. The fact that they may include
generalizing and scientific concepts which otherwise he might not have met at all,
and even the fact that he may face a language-learning task that he might not
otherwise have had to surmount, these considerations are counterbalanced by
two others: first, that his learning load is not X followed by Y, as in the case of
the adult, but rather an amalgam of X and Y; and second, that the learning comes
62 Problems of Language in the <strong>Teaching</strong> of Physics

at an earlier period in his personal development. when concept-formation seems
to be at its most plastic and casual. The adult, on the other hand, faces a learning
load which is truly an addition, and he does so at a different and perhaps less
favourable stage of personal development.
The problem of the pupil who has to use English, French or Russian as a second
language from the beginning of his secondary education has special difficulties :
he is learning the foreign language at the same time that he is learning science; his
science lessons provide part of this teaching of the language; the standard of
language proficiency of the science teacher strongly affects the eventual language
standard of the student. If the rate of progress in science outstrips the rate of progress
in the foreign language. the student may have difficulties 62 his science.
Having discussed the linguistic problems, it would seem appropriate now to
turn to look at the specific problems of language in the teaching of <strong>physics</strong> in
developing countries.
4.5 The dilemma for a developing country*
The modern age is characterized by the increasing impact of science on the lives
of people, particularly in technically advanced countries. Because of this, leaders
in the developing countries have been turning to science for help in their effort to
better the lot of their own people. In the early stages it was thought sufficient to
import some trained scientists, but it was soon realized that science could make
an impact on the life of a country only after it had taken deep roots. Towards
achieving this goal the developing countries are now trying to make science
education more broad-based and more effective. In this context the question of
the medium of instruction assumes great significance.
In <strong>physics</strong> we deal with concepts which are precisely defined. <strong>Teaching</strong> <strong>physics</strong>,
therefore, requires the ability on the part of the teacher to convey the correct
meaning and significance of the concept he wants to teach. On the part of the
pupil it demands a sufficiently deep knowledge of the language to understand
correctly and clearly what is being taught to him. In many parts of the world
today, and especially at the secondary level, <strong>physics</strong> is being taught through a
foreign language and the problem of making a child correctly comprehend the
basic laws and concepts of <strong>physics</strong> is a real one. One can never hope to make a
good physicist out of a student who has not clearly understood basic <strong>physics</strong>.
This may be one of the reasons why, though the number of ‘<strong>physics</strong>-knowing’
people in the developing countries is fairly large, their contribution to the creation
of new knowledge is proportionately much less.
The question as to what should be the medium of instruction has assumed
great importance during the last few decades. There are two possible alternatives
for these countries (a) either to adopt a world language like English or (b) to use
the native language. Both have advantages and disadvantages. English is a
developed language with a tremendous amount of scientific literature and it
might appear easy to teach <strong>physics</strong> through it. However, this would put an extra
* This section was written by L. S. Kothari of the University of Delhi, India.
63 The Dilemma for a Developing Country

strain on the students who wil have to acquire a satisfactory knowledge of this
language. The extent of the difficulty has not always been appreciated by teachers
and some of the problems have been mentioned already in this chapter. On the
other hand, if <strong>physics</strong> is taught through the mother tongue it may be easier for
pupils to follow, but the problem is then that the language may not be sufficiently
developed to be useful for teaching <strong>physics</strong>, particularly in higher classes, because
of the different cultural background against which the language has developed.
There is also the factor that a knowledge of a foreign language such as English
will still be required, especially in higher levels of education, to keep in touch
with the developments in world science.
Pupils must feel at home with the ideas conveyed to them. If they are unable to
understand the basic concepts, and this wil happen more often if the medium of
instruction is not their mother tongue, they may develop an aversion for the subject.
If for some reason such students are forced to continue with <strong>physics</strong>,they
wil start to cram. Even when a student understands the subject he may feel diffident
in expressing his thoughts in his own words and may take refuge in reproducing
the language of some text, which he finds much superior to his own. When he
grows up, it may be difficult for him to outgrow his habit of quoting authority, a
thing not always desirable in scientific discussions.
It is probably a fair assumption that talent is distributed uniformly in the
population of a country. If science in <strong>school</strong>s is taught through a foreign tongue
it wil remain confined to a small minority of the children. This language barrier
wil adversely affect the vast number of children coming from rural areas, and
much talent in the country wil remain untapped. Education in science through
the mother tongue wil provide all with an opportunity to develop their talents.
In spite of the lack of technical literature in the native language and its present
state of unpreparedness to cope with technical subjects, it should be possible in a
fairly short time to make a start towards teaching <strong>physics</strong> through it. This is
because in a sense the language of <strong>physics</strong> is universal. Physics fixes the meaning
of a term whereas language fixes the word for it. Different languages have different
words for ‘ force’, for example, but in each language the meaning of the word
is identical.
In India the problem of the medium of instruction was examined in great depth
by the Indian Education Commission (1966), set up by the Government of India
to study the entire problem of education in the country. In addition to Indian
members, the commission included eminent foreign educationists, from France,
Japan, U K, U SA and US S R. The Commission’s report states :
We are convinced of the advantages of education through the regional languages. W e
regard the development of regional languages as vital to the general progress of the country,
and as an important step towards the improvement of quality in education. To avoid any
misunderstanding we would emphasize that this does not mean the shutting out of English,
or other world languages. In fact, we will profit from these languages all the more when our
education becomes more effective and useful.
64 Problems of Language in the <strong>Teaching</strong> of Physics

India of course is a multilingual country; fifteen different languages are recognized
by the constitution. In such countries scientific terminology lies on three
different levels (a) international terms, (b) terms common to all languages of the
country and (c) local terms. Conceptual words like energy. force, mass. etc. will
generally have equivalents which differ from language to language. These are the
’ borrowed words’, borrowed from ordinary speech and given a precise meaning
in science. The other class of ‘invented words’, i.e. words invented or imported
specially for scientific purposes, may be common to all languages of the country
and may be close to the international term. In the early stages of the spreading of
science in a country the proportion of local terms wil have to be kept high, but
this can gradually be reduced and the proportion of international terms increased.
In order to accelerate the use of Indian languages as media for instruction in
science subjects, a special Commission for Scientific and Technical Terminology
(Kothari, 1964) made specific recommendations, including the following, which
might be of benefit to other developing countries:
In the Hindi terminology as also in other languages. the ‘international terms‘ (e.g. names
of elements. compounds. physical units and constants. and mathematical operations)
should be adopted, transliterated wherever necessary to suit the grammar and structure of
Hindi, in their current English form, unless there are compelling reasons to the contrary in
the case of any particular term.
Numerals. symbols. signs and formulae employed in mathematics and other sciences
should be adopted in their ‘international form’ without modification.
Effective steps should be taken to ensure in the terminology work the active participation
of the users of the terminology (<strong>school</strong> and college teachers).
Once it is recognized that in developing countries science should be taught in
the local languages, every effort should be made to help them enrich their
scientific literature. In the advanced countries various attempts have been made
to revise the <strong>school</strong> <strong>physics</strong> curriculum and also the method of teaching. Amongst
the programmes that have drawn world attention are P S S C, Harvard Project
Physics and Nufield Physics. The PSSC text has been translated into many
languages, but it is apparent that in a developing country, using a translated version
of such a text is not satisfactory, since a textbook, particularly for the <strong>school</strong>
level, is always written keeping in mind the social background of the children
who will use it. and this differs widely from country to country. But there is a
need for monographs written by experts on current topics for the use of <strong>school</strong>
teachers and students, which could be made available cheaply and translated into
other languages.
The advantages of teaching <strong>physics</strong> in the mother tongue have already been
stressed. The fraction of the world population aware of science is very small. It
will need a major revolution in science education if the still dormant talent of the
vast humanity in developing countries can be provided with opportunities to
contribute effectively to science and through this benefit all countries. A major
step forward will be made when science can be taught in the pupil’s mother
65 The Dilemma for a Developing Country

tongue. On the other hand, it wil certainly remain necessary for pupils in secondary
<strong>school</strong>s, especially those wanting to go to higher studies in science or engineering,
to acquire a good knowledge of English, and maybe also of Russian, if they
are to keep up with growing knowledge.
For this reason, the establishment of closer links between science teaching and
language teaching would appear essential and these are discussed in the final
section of this chapter, contributed by Professor Strevens.
4.6 The need for closer links between language teaching and science teaching
It is not at all certain how far the learning of science and its concepts in a second
or foreign language is made more effective by the manner of its teaching. What is
almost universally the case is that foreign languages are taught with aims unrelated
to science, and even where the foreign language is used in the teaching of
science this is done with little professional acknowledgement of the special conceptual
tasks facing the learner. ‘First he learns English (or French, etc.); then
he is taught science as if he was an English pupil.’
The underlying educational policy is to teach the foreign language to all the
members of a certain section of the population, and to select from among them,
after they have been learning English for a given period of years, a further subset
who will then be taught science. But the aims of teaching English to a major
group of learners have almost always been defined in terms of general culture :
these terms are in practice largely literary. Even where lip-service is paid to the
need for a foreign language as a tool, as a means of communication, or as a force
of cohesion, analysis of the English syllabus nearly always reveals that it is leading
up to the study of Shakespeare, Wordsworth or Dickens, and that its concepts
are the subjective, aesthetic ones of literary studies. In many cases, too, the
bias of the syllabus and teacher alike is openly anti-scientific, rejecting detailed
observation in favour of the subjective response.
It is not the purpose here to criticize these attitudes for their own sake. But if
we look at the education of scientists we discover that before they start to learn
science a great number of overseas learners are first taught a foreign language
according to syllabuses that are in some sense opposed to the attitudes of science.
What is worse, in most countries the general effectiveness of the teaching of a
second or foreign language, although it may be better than it was fifty years ago,
is by no means satisfactory or even encouraging. The results of this are reflected
at least partly in the short-fall in the education of scientists, engineers, technologists
and fitters.
It can be argued that a high proportion of the teaching and learning effort in
the foreign language which students of science undergo before they embark on
science is wasted. Much of it is wasted because it is irrelevant to the needs of the
scientists; some is wasted because it is ineffectively learned and taught.
Bringing together the various considerations raised in this chapter so far, it is
possible to suggest that a measurable, and possibly major, increase in the
effectiveness of science education might be achieved if the priorities were reversed,
so that the foreign language was taught for science and through science in the
66
Problems of Language in the <strong>Teaching</strong> of Physics

first instance, with special attention being paid to the deliberate inclusion of the
generalizing concepts in the language course, as well as the special concepts of
science. Not all pupils would show the ability or the preference to follow advanced
courses in science. Those who fall by the wayside would be selected for
the continuation along general cultural and literary lines. Under this strategy all
learners would have the opportunity to achieve their potential in science, and
only a minority would study literature, instead of the other way round. This
seems to make much better sense in the condition of most developing states.
A science-oriented language syllabus is entirely feasible. All the basic teaching
of a foreign language can just as easily be placed in the framework of learning
science as in a framework of everyday discourse (which is in fact what the present
syllabuses teach in the early stages). Of course the syllabus must take account of
the age and interests of the learner, but there are few existing English or French
courses that would not be improved and rendered vastly more interesting to the
learners by (for example) replacing stories of King Arthur and the Round Table
by extracts from current science fiction, or replacing scenes from the French
Revolution by texts about supersonic flight or the potentialities of computers.
Much of the effort currently expended in teaching potential engineers in tropical
Africa about daffodils or about manners in nineteenth-century England could
with profit be rechannelled through syllabuses whose ultimate aims include the
preparation of citizens with adequate scientific and technical understanding.
Envisaged here is the creation of a syllabus and of a full range of teaching
materials for particular levels and age-groups, in which English or a foreign
language would be taught from the beginning in the framework of a science
course, and science would be taught in English. In such a syllabus the choice of
linguistic content would be determined in the first instance by the requirements
of the science syllabus; the various categories of concept-formation discussed in
this chapter would receive deliberate treatment; accompanying materials would
all be geared to the aim of exploiting to the maximum the science potential of
each learner.
Such a course of action would face considerable difficulties, not only in its
preparation but also in the retraining of teachers. Many teachers would find it
difficult to adjust their outlook from the artistic imprecision of a ‘generalcultural’
base. The administrative problems would also be great. Nevertheless in
the present state of affairs only some such drastic remedy seems likely to provide
a sufficient improvement in the effectiveness of science education in the developing
countries, at least until such time as it really becomes feasible to teach science
effectively at the secondary level through the mother tongue.
To sum up, language teachers ought to become aware of the extent to which
certain parts of their language syllabus are an essential prerequisite for those of
their pupils who learn science; while teachers of science ought to become aware
that many of the errors which their pupils commit are due to inadequate grasp of
language rather than inadequate grasp of science. And the more collaboration
there is between teachers of different specialities, the better for the teaching of
science, and above all, the better for the pupils.
67 Need for Closer Links between Language <strong>Teaching</strong> and Science <strong>Teaching</strong>

Part Three
Approaches to Content and
Method

5 How to Teach Physics
No apology is made for opening this important chapter with an account written by an
East African boy. Its charm will.we hope, appeal to readers of thisvolume and there are
lessons to be learnt from it. al the more eloquent for its lack of sophistication.
The edited chapter is based on contributions from Thomas D. Miner. Fletcher
G. Watson, W. R. Ritchie, K. Hecht, L. S. Kothari and V. J. Long.
5.1 Rate of cooling
Erasto B. Mpenibn
My name is Erasto B. Mpemba and I am going to tell you about my discovery. In 1963,
when I was in form three in Magamba secondary <strong>school</strong> (in Tanzania), I used to make icecreams.
The boys at the <strong>school</strong> do this by boiling the milk and mixing it with sugar and
putting it into the freezing chamber in the refrigerator, after it has first cooled nearly to
room temperature. A lot of boys make them and there is a rush to get space in the refrigerator.
One day after buying milk from the local women, I started boiling it. Another boy, who
had bought some milk formaking ice-cream. ran to the refrigerator when he saw me boiling
my milk, and quickly mixed his milk with sugar and poured it into the ice-tray without
boiling it. so that he may not miss his chance. Knowing that if I waited for the boiled milk
to cool before placing it in the refrigerator I would lose the last available ice-tray, I decided
to risk ruin to the refrigerator on that day by putting hot milk into it.
The other boy and I went back an hour and a half later, and found that my tray of milk
had frozen into ice-cream while his was still only a thick liquid. not yet frozen.
I asked my <strong>physics</strong> teacher why it happened likethat, with the milk that was hot freezing
first, and the answer he gave me was that, ‘You were confused, that cannot happen.’
After passing my 0-level examination. I was chosen to go to Mkwawa High School in
Tringa. The first topics we dealt with were on heat. One day as our teacher taught us about
Newton’s law of cooling. I asked him the question ‘Please, Sir, why is it that when you put
both hot milk and cold milk into a refrigerator at the same time. the hot milk freezes
first?’ The teacher replied, ‘I do not think so. Mpemba.’ I continued, ‘It is true, Sir.I have
done it myself,’ and he said, ‘The answer I can give is that you were confused.’ I kept on
arguing, and the final answer he gave me was ‘Well, all I say is that that is Mpemba’s
<strong>physics</strong> and not the universal <strong>physics</strong>.’ From then onwards if 1 failed in a problem by
making a mistake in looking up the logarithms this teacher used to say, ‘That is Mpemba’s
mathematics.’
71 Rate of Cooling

And the whole class adopted this, and anytime I did something wrong they used to say
to me, ‘That is Mpemba’s. . .’,whatever the thing was.
Then one afternoon I found the biology laboratory open, and there was no teacher.
I took two 50 cm3 small beakers, one I filled with cold water from the tap and the other with
hot water from a boiler; and quickly put them in the freezing chamber of the laboratory
refrigerator. After one hour I came back to look, and I found that not all the water had
been changed into ice, but that there was more ice in the beaker which had hot water to
startwith than in the one which had cold water. This was not really conclusive. So, I planned
to try it again when I had the chance.
When Dr Osborne visited our <strong>school</strong> this year, we were allowed to ask him some questions,
mainly in <strong>physics</strong>. I asked, ‘If you take two similar containers with equal volumes of
water, one at 35 “C and the other at 100 “C, and put them into a refrigerator. the one that
started at 100 “C freezes first. Why?’ He first smiled and asked me to repeat the question.
After I repeated it he said, ‘Is it true, have you done it?’ I said ‘Yes.’ Then he said, ‘I do
not know, but I promise to try this experiment when I am back in Dares Salaam.’
Next day my classmates in form six were saying to me that I had shamed them by asking
that question, and that my aim was to ask a question which Dr Osborne would not be able
to answer. Some said to me, ‘But, Mpemba, did you understand your chapter on Newton’s
law of cooling?’ I told them, ‘Theory differs from practical.’ Some said, ‘We do not
wonder, for that was Mpemba’s <strong>physics</strong>.’
I asked the head of the kitchen staffat <strong>school</strong> to let me use a refrigerator for this experiment.
She gave me the use of one whole refrigerator for a week. First I did the experiment
by myself, because I was afraid that if I failed anyone else would tell the whole <strong>school</strong> that I
was just stupid on that day when I asked the question. But my results were the same. The
following day I took three boys with me from among those who had scorned my question
and performed. the experiment. We found that ice started to form first from the hot milk.
These three boys laughed very much and started telling the others that I was right, but
that they could hardly believe. Some said it was impossible. I told the head of the <strong>physics</strong>
department in my <strong>school</strong> that the experiment had worked; he then said, ‘It should not, I
will have a go at it this afternoon.’ But later, he found the same result.
The sequel is described by Professor Denis Osborne, the head of the <strong>physics</strong>
department of the University, Dar es Salaam, for whom the above account was
written.
The headmaster of Mkwawa High School invited me to speak to the students on <strong>physics</strong>
and national development. I spoke for half an hour, but questions lasted for a further hour.
There were questions of personal concern about entering the university, loaded questions
about the remote possibility of relating parts of the <strong>school</strong> <strong>physics</strong> syllabus to national
development, and questions that showed a considerable breadth of reading including one
on gravitational collapse. One questioner raised a laugh from his colleagues with a question
I remember as; ‘If you take two beakers with equal volumes of water, one at 35 “C and
the other at 100 “C .. . Why?’. It seemed an unlikely happening, but the pupil insisted he
was sure of the facts.
Now I enjoy answering questions and want to encourage questioning and critical
attitudes. No question should be ridiculed. In this case there was an added reason for
caution, for everyday events are seldom as simple as they seem and it is dangerous to pass a
superficial judgement on what can and cannot be. I said that the facts as they were given
surprised me because they appeared to contradict the <strong>physics</strong> I knew. But I added that it
was always possible that the rateof cooling might be affected by some factor I had not con-
72 How to Teach Physics

sidered. I promised we would put the claim to the test of experiment at the University
College and urged my questioner to repeat the experiment himself.
At the University College in Dar es Salaam I asked a junior technician to test the facts.
The technician reported that the water that started hot did indeed freeze first and added in a
moment of unscientific enthusiasm, ‘But we’ll keep on repeating the experiment until we
get the right result.’
Further tests vindicated the pupil’s claim and Professor Osborne set about
finding an explanation which is published in Physics Edzicatiorz (Mpemba and
Osborne, 1969). The details of the <strong>physics</strong> do not concern us here but this
delightful account enables one to draw many morals. especially in a chapter on
how to teach <strong>physics</strong>. The danger of the dogmatic approach of the first teacher,
the evils of sarcasm in teaching, the picture of Professor Osborne asking the
questioner to repeat the question to give him time to think and his wise handling
of the situation to avoid discouraging a critical, scientific attitude, the cooperation
of the ‘ head of the kitchen staff’ in allowing the use of a refrigerator for a
week of investigation, are all indicators to what is good and bad teaching. And of
course there is the final gem of the technician promising to go on repeating the
experiment ‘until we get the right result’. At least the above points to the danger
of an authoritarian <strong>physics</strong>.
5.2 <strong>Teaching</strong> <strong>physics</strong>
A discussion of the teaching of <strong>physics</strong>, or the teaching of any subject, necessitates
consideration of at least three topics: what will be taught and why, to
whom it will be taught and why. and how it wil be taught and why. A general discussion
about <strong>school</strong>ing could begin with any one of three components: what,
to whom, how. Although all three aspects must be considered, quite different
types of emphasis and course structure are likely to result if we begin with oneparticular
aspect and make the other two subservient. In fact a course design based
initially on one of these three factors wil have to be modified as the others are
seriously considered. However a start must be made somewhere and this chapter
wil be concerned mainly with how. What to teach wil be left to the next, although
it must be realized that these are not in fact independent of each other.
5.3 Learning <strong>physics</strong>
In the emphasis that we as teachers often place on pedagogy we may overlook the
fact that teaching only has merit when it results in learning. When teachers complain
about lack of time to teach a course they may not recognize that it is learning
not teaching that takes the time, and when a topic is characterized as ‘difficult’
what is meant is that the learner has trouble with it. Teachers must thus focus
their attention on the pupil’s learning, and no teaching procedure, however
logical and elegant. can be considered worthwhile unless it promotes learning.
The kind of learning that is desired must also be examined. Facts are an important
part of our education but are soon selectively forgotten. Although we
73 Learning Physics

must deal with facts, we must not regard the acquisition of facts as the prime goal
of teaching. Concepts, being intellectual patterns based on facts, may last longer.
The highest goal of teaching is achieved when the facts and concepts that are
listed in the course syllabus have become so much the possessions of the learner
that his view of the world is affected; his attitudes and style of thought have been
changed. The teacher who can accomplish this has achieved a kind of immortality.
5.3.1 Physics as a human activity
Physics as a subject to be learned suffers from some unusual handicaps and
enjoys some unique advantages. <strong>Teaching</strong> and learning as human activities
depend in the classroom on encounters between people, pupils and teacher,
pupils and pupils, and involve the inevitable emotional element of human reactions
to other people. On the other hand <strong>physics</strong>, the subject being taught and
learned, has the reputation of cold precision, rejecting such human features as
emotion and taste in making decisions. Much of the public, and unfortunately
some <strong>physics</strong> teachers, see <strong>physics</strong> as inhumanly impartial, an exact body of
exact knowledge presented in mysterious symbols, embodying certain inviolable
laws against which all observations must be weighed and capable of yielding an
unequivocal answer to any physical problem, given time. The teacher who by his
own behaviour supports this misapprehension is not only presenting a false view
of <strong>physics</strong> but is actively discouraging the learning of the subject.
What are some of the characteristics of <strong>physics</strong> and physicists that a teacher
can stress in his classroom to help his students gain a clearer and truer vision of
<strong>physics</strong>?
The crux of the matter is that <strong>physics</strong> is a human activity. It is carried out by
people, not by automatons or computers. Physicists laugh when amused, cry out
when hurt, are elated and discouraged on occasion and throw most of their work
into the wastebasket. Men who have made major contributions to <strong>physics</strong> have
ranged in character from unworldly saints to earthy scoundrels. Their pastimes
are recognizable, extending from motorcycling and mountain climbing to bridge
playing and music making. Some raise families, others are celibate, and they
range in belief from atheistic to devoutly religious. If pupils are to understand
<strong>physics</strong> as one of the highest types of learning they must’relate <strong>physics</strong> and
physicists to themselves. The average person can easily identify with physicists
as they really are.
5.3.2 The role of the teacher
The <strong>physics</strong> teacher, as the only physicist known to most of his pupils. must avoid
the role of imperious know-all ‘master of mysteries’. He must not conceal errors
that he makes at the chalkboard, nor gloss over demonstration results that do not
show what he intended. He must not scorn or ridicule the errors of others or overwhelm
the ‘stupid’ questioner with sarcasm. In developing new ideas he must
74 How to Teach Physics

carry the class along with his own thoughts rather than presenting them dogmatically
as if they were divine revelations. Physics must be shown as it is: a tentative
and questing process, an approximation created by human minds in which
every question answered raises more questions.
5.3.3 The avoidance of magic
Another way in which the <strong>physics</strong> teacher can work to overcome the unfortunate
public image of <strong>physics</strong> and promote true learning is to remove from his course
all elements of magic. Anything is magic if a result is achieved by seemingly
supernatural means; by what appears to be inexplicable mastery of secret forces.
Physics lends itselfall too well to this sort of approach. The algebraic formula
that when supplied with numbers yields the ‘correct’ answer need not be understood
to be used. The pat definition or slogan-like statement of a law need only
be memorized as one might learn a magical incantation in order to satisfy certain
types of examination questions. An example of such a hackneyed statement,
usually quite meaningless as memorized, is ‘ For every action there is an equal and
opposite reaction.’ What <strong>physics</strong> teacher has not met pupils who felt comfortably
secure with these words without knowing the meaning of ‘action’? Formulas
should be presented to the <strong>physics</strong> pupil as tools to be used only after comprehension,
and an effort be made to discourage rote learning by never stating a definition
or law twice in exactly the same words.
At a different level of magic is the pretty or amazing demonstration that conceals
in its complexity the principle supposedly being demonstrated or works for
no understandable reason at all except to gratify the demonstrator’s sense of
showmanship.
Teachers sometimes devise clever demonstrations whose major effect is to trick
students into an incorrect response, and this is another technique of the magician
or entertainer, not of the teacher. It is possible, for instance, to present a standard
demonstration, such as Galileo’s interrupted pendulum, in such a way that practically
all students will be trapped into thinking that the bob must rise higher after
the string strikes the obstruction than when swinging freely. It may be fun to be
fooled and satisfying to learn how the deception was worked. perhaps even
instructive to find that one can be so easily misled, but whatever gains are realized
for this one situation are cancelled by the suspicion of trickery that wil envelop
future demonstrations which may have unexpected features. Many teachers,
some in very exposed positions, have mistaken the attention given to them as
entertainers for interest in their subject.
5.3.4 The respomibility of the teacher
Classroom climate and the methods of teaching have a significant effect on the
types of learning achieved by various pupils. As might be anticipated, and as has
now been shown by recent research investigations, a teacher-dominated. highly
organized and essentially single-track approach results in fairly high learning of
75 Learning Physics

the specific details of the <strong>physics</strong> being taught and relatively low gains in understanding
the nature of science and its interaction with society. Where classes are
operated so that pupils have more choices, on the average they wil learn a bit less
of the details of the <strong>physics</strong> but considerably more about how science is created
and how its ideas relate to the general culture. As would be expected, and has
been confirmed by research, the teacher’s method of teaching is related not only
to his personality but also to his view of his responsibilities and his view of how
pupils learn.
As every teacher knows, there are times when the pupil must be taught individually
as though being tutored. Such encounters may be brief, but critical. The
teacher needs to develop the skill of observing his pupils, knowing them personally
as complex individuals. Observation leads to diagnosis and the decision
on the best treatment, whether it be more individual attention or giving more
independence to the learner. Teachers therefore need not only to understand
<strong>physics</strong>, but also to be skilled in pupil observation, diagnosis of trouble and the
selection of appropriate action.
5.4 The role of mathematics
Physics teachers often complain of the mathematical insecurity of their pupils
and such complaints are in many cases justified. We must not however forget that
people do not ordinarily use symbols and algebraic processes in thinking and
communicating - few of our students wil be professional physicists or mathematicians
- and far more important than the rigorous symbolic statement of a
principle is its verbalization. We probably do not need more mathematics in our
introductory <strong>physics</strong> classes but instead more carefully chosen and more
meaningful words. This is not to say that the quantitative aspects of <strong>physics</strong> can
be ignored. It is of course a fact that the understandings we know as <strong>physics</strong> are
rooted in quantitative observations and that hypotheses stand or fall as they are
tested by comparing numerical results. Mathematical expressions aid us by providing
a numerical shorthand for making concise and precise statements, and
mathematical operations are an invaluable aid to reasoning. No new knowledge,
however, can ever emerge from a mathematical manipulation. The knowledge is
contained in the data or assumptions with which the process started. We gain
instead an increase in insight and intelligibility, a revelation of consequences,
conditions and limitations.
If we are, however, to consider the less superficial aspects of learning, we must
recognize that unused mathematical skills decay quickly and that in the long run
symbols and equations are no substitute for words. For the beginner a foreign
language requires translation to his own tongue, and similarly mathematical
statements require translation to the usual language of thought, words and sentences.
Careful verbalization, avoiding clichks, can contribute to lasting understandings.
76 How, to Teach Physics

5.5 Techniques of teaching
How a course is taught will determine to a large extent what the pupil takes away
from it to retain during subsequent years. The design of a course, and all the
accompanying paraphernalia of <strong>books</strong>, experiments, apparatus and films,only
make available to the teacher possible ways of proceeding. They guarantee
nothing to the pupil: he may perhaps receive more 'up-to-date' information, but
the experience can still be dull and irrelevant, and the new course can still be
taught in the same old way, unless the teacher comprehends the rationale of the
new course and develops the techniques required.
If the intention of a course is to give factual knowledge, one technique wil be
adopted. But the emphasis in all the discussion throughout this volume is away
from the mere acquisition of factual knowledge and towards the development of a
critical approach. A god-like figure of a teacher who knows all the answers may
be good for the self-esteem of the teacher, but. in the first place, he does not in fact
know all the answers (as shown in Erasto B. Mpemba's contribution at the beginning
of the chapter) and, secondly, such an attitude discourages critical thought
on the part of the pupil. There is great virtue in stopping the teacher from talking
too much! A wise teacher. even when he does know, should be able to lead the
pupil to think out the answer for himself without giving it to him directly. Of
course this takes longer - and this is one reason for not overloading the course -
but the gain in self-confidence and self-reliance, which some teachers think may
develop from this technique. outweighs other considerations.
When the pupil leaves <strong>school</strong> he wil not continue to have an all-knowing
teacher at his side and we must prepare him for that stage. Even if he is doing
research work, all he can hope for is advice and helpful suggestions from others.
If he is solving problems back in his rural community, there will be no standard
solutions to those problems which he can get from one person. We must prepare
pupils for these situations and there is much virtue in the role of the teacher
changing from the fount-of-all-knowledge to the consultant with whom one's
problems can be discussed. In practice this often means not answering a question
but raising another, intended of course to lead the pupil himself towards the
solution.
This technique is particularly important in laboratory work. There is little
value in following 'cookery book' instructions, whether from a book or dictated
by the teacher: the value lies in doing an investigation and in having to think. But
the same technique is valuable in class discussion as well.
However, this view would not be shared by everyone and one contributor to
this chapter, Thomas Miner, writes strongly as follows.
One of the most abused of all teaching techniques is that of developing new ideas by
questioning students, or of answering questions with questions. There are some legitimate
uses for this approach. Its advocates maintain that it requires students to think. that concepts
arrived at this way are better understood and longer retained because the teacher-.
questioner has developed them from the student's own background and observations. It
may indeed be the best approach, especially in a one-to-one situation and in the hands of a
77 Techniques of <strong>Teaching</strong>

very skilled teacher. In a class, however, the procedure of eliciting from the students a
desired line of thought has wasteful and even dangerous aspects. It-is not profitable to have
an entire class misled by the random response of an inattentive student. The mistaken
reasoning of one student should not be allowed to block or distract the thoughts of all his
fellows. The time required to lead a class to the point at which they can establish a concept
themselves may be entirely out of line with the gains. Where a teacher habitually uses this
approach the more aware members of the class learn what is expected of them, the whole
process becomes ritualistic and the procedure gets more attention than the hoped-for
result. It is questionable whether a series of mental processes dictated by another can build
habits of independent thought.
Answering a question by asking questions has the added danger of discouraging students
from asking questions, and this is a severe loss. The student who asks for information or
help wants and deserves an answer. When he is led by questions through what the teacher
thinks should have been his original line of thought the answer is at best deferred. The
bright student becomes impatient, the dull student is baffled and the sensitive or timid
student wilts when he is required to play the teacher’s game this way.
Answering questions and developing ideas by asking questions is sometimes termed
‘Socratic’. Socrates used his questions with a purpose essentially destructive: to show that
his victim did not reallyknow what he thought he knew. Socrates elicited concessions and
trapped his listenerinto expressing contradictory opinions. Destroying cherished misconceptions
is often among the duties of the <strong>physics</strong> teacher, and for this purpose true Socratic
questioning is a useful teaching method.
From this it should be clear that there is no unanimity about the best techniques.
Flexibility to meet the actual classroom situation is perhaps what matters
: some teachers do not like the answering of one question by asking another;
others find it does exactly the opposite of what is claimed above and encourages
rather than discourages further thinking.
5.5.1 The lecture
The pure stand-up lecture can be very unsuitable for introducing <strong>physics</strong>. Its
advocates like it because it is easy for the teacher and efficient in that a lot of
ground can be covered quickly. But learning is an activity. The mind should not
be treated as a passive receptacle, but must be actively engaged. Covering subject
content ‘efficiently’ is emphasizing teaching at the expense of learning. Very
few teachers have students who are accomplished enough as listeners or can
themselves speak with sufficient effect to make lecturing a good method of
presenting <strong>physics</strong>.
As with other arts, it is easier to say what is not right in teaching than to
describe a best procedure. This is one of the fascinations of teaching: it gives rein
to individuality, but demands discipline. There is no single best way of teaching,
but there are many good ways, each suited best to the ability and personality of
the teacher and to the characteristics of his students.
There is, however, an identifiable atmosphere to a classroom in which <strong>physics</strong>
is being learned, no matter what teaching technique is being applied. In most
classes like this the teacher is not telling the students by lecturing, nor probing
78 How to Teach Physics

students’ minds by questioning, but is himself thinking out loud and drawing
students’ thought along. His questions invite their participation, his statements
challenge their intelligence. his handling of chalk and apparatus is such as to
demand student involvement in his own thoughts. When this is achieved physical
facilities, equipment, texts and even the syllabus become mere auxiliaries. and the
human interaction between teacher and students is the central operation of the
learning process.
5.5.2 Iiidioidzrul iristrucf ion
In the United States of America there is now increasing discussion about the need
to ‘individualize instruction’. We all recognize that each person learns individually;
nobody can do the learning for him. Many of the new courses which
stress ‘individualized instruction’, particularly in science programmes developed
for elementary <strong>school</strong>s or junior high <strong>school</strong>s (pupils aged 12-14). establish a
very narrow and rigid sequence of experiences and conclusions through which the
pupil is to progress at his own rate. The ‘individualization’ is primarily in terms
of the pupil’s rate of progress over a particular set of pre-established hurdles.
Such a course is highly structured and permits few, if any, deviations or accommodations
to the particular interests of individual pupils.
An extreme alternative would be an exceedingly open course with essentially
no boundaries. It would be based upon certain selected classroom materials
which the child would manipulate and from which he would, it is hoped, draw
questions worthy of his own efforts to investigate. Here the initiative lies entirely
with the pupil, but one wonders what he is learning and whether some other types
of inputs might not also be useful. The question is then how to steer a course
between the Scylla of highly structured materials on one side and the Charybdis
of a very open programme on the other side. One possible solution, which is a
useful compromise, lies in what has been done in Harvard Project Physics. It
provides a wide diversity of instructional materials from which pupils can make
choices but which are bounded by a common set of scientific concepts being
communicated through the various media.
This rich diversity of instructional materials includes about three times as
much as any single pupil could use effectively. Choices, either by the teacher or by
the pupil, are necessary. This guarantees that the teacher not only can. but must,
shape his own individual course, and at the same time allow pupils working in
small groups or individually to make their own selections. Thus there is freedom
within restraints. There is not a straight-lined course through which each student
must proceed, even at individually varying rates, but rather a set of diverse
materials from which teachers and students can shape their own courses.
5.6 Stages of understanding
Pupils often accept new ideas very readily through a sense of familiarity. Many
people have a working acquaintance with electrical circuits but would be hard
79 Stages of Understanding

put to it to explain in words what they are doing and why. We tend to use the
word ‘ energy’ boldly, but seldom ‘entropy’. In fact the first concept is as difficult
as the second, but common use has taken the fear out of the first.
Beyond this initial sense of familiarity comes a different quality of understanding,
when suddenly the pattern seems to fit together; the theories are seen
to enlighten the facts; the whole issue becomes reasonable. Every good teacher
rejoices to see the light dawn in a pupil’s eyes, to overhear him say to his neighbour
‘I never understood that before.’
It does seem necessary for most of us to proceed to the second, higher level via
the first. Only a few powerful thinkers can grasp at once the fullness of a great
generalization (though this power does seem to increase with training). Psychologists
find that the hill of learning for most of us has to be a series of steep ascents
with plateaux in between: we need periods of digestion between meals. It is significant
that the Nuffield and related courses are designed for this staged growth.
For example, the basic concept of energy is developed a little further each year. It
begins with little more than a nodding acquaintance with energy-transforming
machines; this acquaintance is increased the following year when simple
measures of energy are introduced, later becoming more involved; finally a
strenuous effort is made to satisfy pupils that what may seem quite alien measures
can all be used for the same thing. This ‘ spiral’ approach in teaching, starting
from simple ideas and increasing in subsequent years to greater sophistication,
can be applied to most concepts, such as force, electric currents and the wave
interpretation of radiation.
5.7 The influence of objectives on how to teach*
A distinction has to be made between (a) teaching the content of <strong>physics</strong>, i.e.
imparting that body of knowledge which can be said to constitute the subject,
and (b) teaching for an understanding of how the physicist thinks, i.e. how he
proposes hypotheses, builds mental pictures (or models) to explain the nature of
the empirical world around him and how he then confronts these ideas with experience
by designing experiments to test the predictive power of a theory which
may result in its modification.
A course which is not aimed primarily at the future physicist but at the future
educated layman should attempt to show that:
(i) <strong>physics</strong> has both experimental and theoretical bases, which have their limitations
;
(ii) physical principles can explain commonly observable phenomena ;
(iii) a physicist tackles problem situations using various techniques ;
(iv) <strong>physics</strong> is not a collection of dry facts. It is not memory or magic but disciplined
curiosity. It is a human endeavour relevant to modern technology, vital to
our economy and having tremendous social impact.
* This section was contributed mainly by W. R. Ritchie of the Scottish Education Department
80 How to Teach Physics

It is impossible to begin to discuss how to teach <strong>physics</strong> without first deciding
on the broad aims of the course of study and then expressing these, if possible, in
behavioural terms so that clearly defined objectives are stated. For example, the
following hierarchy of cognitive objectives, based on Bloom (1965), is restated
here in terms of <strong>physics</strong>.
Table 1 *
A B C D
K?iow~ledge Coinpreheiision Application Highest Abilities
-
Recall of useful Ability to apply Ability to apply This broad category
information. a principle to a a principle to a (Bloom 4. 5 and 6)
not inert or situation which situation which will include :
inoperative
ideas
it is reasonable
to expect most
pupils to have
encountered in
class and where
it is obvious to
the pupil which
principle should
be used
most pupils
would not have
encountered in
class and where
the pupil must
first select the
appropriate
principle
the ability to apply
principles to problem
situations, the
solution to which
involves two or
more stages;
the design of an
experiment and/or
the selection of
apparatus of
suitable type, range
and sensitivity;
the critical appraisal
of measurements and
the interpretation of
data
* This table has been used by the Scottish Certificate of Education Examination Board for the new
<strong>physics</strong> teaching in Scotland.
The selection of relevant <strong>physics</strong> content is then required to act as a vehicle for
these objectives. The first point to emphasize is that it is important to avoid
selecting so large a sample of content, of electricity, mechanics and so on, so that
the teacher is forced to teach in such a way that he has to rush through the course,
with the more complex thinking processes inevitably sacrificed in the interest of
content coverage.
It is wise to display the chosen content and objectives on a two-dimensional
grid, as shown in Table 2. It is too easy otherwise for the busy teacher to get
absorbed in objectives A and B and to neglect objectives C and D. The X shown
81 The Influence of Objectives on How to Teach

start
in the table indicates that one specific objective is the ability to apply certain
energy principles in an unfamiliar context.
Table 2
Content
Energy
Waves
D.C. Electricity
...
Objective A B C D
x
Given suitable objectives, important decisions then have to be taken concerning
their relative importance. This in turn affects the orientation of the teaching
towards either an authoritarian approach on the one hand or a ‘heuristic’
approach on the other. The different approach involved in each is summarized in
Table 3. There are of course many possible standpoints between these two
extremes.
Table 3
1. Authoritarian 2. Heuristic
(i) The learning process is the
acquisition of knowledge
(ii) Formal instruction
(iii) Effort leads to interest
(iv) Demonstration experiments and
‘ chalk and talk ’ lectures
(v) Verification of stated laws
(vi) Practice in standard examples
(i) The learning process is the
acquisition of experience
(ii) Learning by doing
(iii) Interest leads to effort ~ from
pupil’s present needs and interests
(iv) Pupil experiments
(v) Problem situations investigated ~
discovery methods
(vi) Application of principles to novel
situations
It is generally agreed that approach 1 is more suitable for realizing objectives
A and B while approach 2 is more likely to encourage the mental processes C
and D. In 2 the pupil is continually placed in the position where he has to select
appropriate knowledge, apply it and exercise judgement in appraising data
82 How to Teach Physics

gleaned from the experiments he has designed. This approach allows the pupils
to make mistakes (necessarily a corollary of learning to create and evaluate) and
is therefore more costly in terms of staff/pupil ratio, time, laboratory facilities,
equipment, laboratory assistance ~ and the teacher’s nervous system.
Another decision concerns the organization of the learning experiences in
some chronological sequence. Reference to this has been made already in this
chapter. Two extreme approaches can be identified.
Table 4
1 2
Logical progression through
syllabus
Linear construction
Precise definitions at start
Mathematical and quantitative
approach all through
(i) Sequence based on psychological
grounds
(ii) Concentric or spiral construction
(iii) Definitions evolved at the end ~
words used in context at the start
without definition
(iv) Qualitative approach at start,
sharpening up mathematically
later
In approach 2 continuity of thought is preserved by the reiteration of concepts
at intervals of say a term or a year. Each time the concept reappears within this
cyclical development a greater depth of understanding develops. In approach 1,
on the other hand, each part of the syllabus deals with a particular topic, which is
then built upon without necessarily recurring in later parts of the course.
Educational writers who have pronounced on this problem include, for example,
Whitehead, Piaget and Bruner. Whitehead thought that education consisted
of a cyclical process including three stages (a) romance, which allows ‘the
sudden perception of half-disclosed and half-hidden possibilities ’. (b) precision.
once some momentum has been gained in the earlier stage and (c) generalization,
since knowledge gained should not be kept in cold storage and pupils should experience
the power of using ideas. Piaget’s work requires that cognisance is taken
of the pupil’s readiness, or lack of it, for learning at a particular stage of development.
Bruner’s ideas involve the structure of a subject as well as readiness.
intuition and motivation. All of this must be carefully considered.
Extremes of authoritarian and heuristic approaches can be avoided: a compromise
is possible, which might be called ‘stage-managed’ or ‘guided’ heurism.
This is the approach adopted in new programmes in Scotland, for example, where
it is combined with a spiral treatment as outlined above. This programme is discussed
in the case histories later in this volume (Appendix B.14).
In conclusion, it cannot be stressed too strongly that it is in fact the objectives
of a course that must decide how the <strong>physics</strong> is taught. If the object is the acquisi-
83 The Influence of Objectives on How to Teach

tion of factual knowledge, demonstration experiments and ‘chalk and talk’ may
be adequate. If the objectives are wider, then some of the other techniques discussed
in this chapter become important. There is of course another important
aspect of the educational process, in addition to the objectives and the learning
experience, namely evaluation. If one of the three components is inappropriately
constructed the other two wil suffer. For example, if an evaluation exercise supplied
by an examination board does not reflect the course objectives then the
type of learning experience provided wil certainly be affected. It is useless to
state complex objectives and then set examinations asking for little more than
recall. Methods of evaluation therefore have a profound effect on how <strong>physics</strong> is
taught, but this is left to a later chapter in this volume.
84 How to Teach Physics

6 What to Teach:
Some General Principles
What to teach in a <strong>physics</strong> course is closely linked with the reasons why <strong>physics</strong> is taught
at all.It is an almost impossible task for anyone to write a chapter such as this, for every
physicist will have his own ideas on the essential content of a secondary-<strong>school</strong> <strong>physics</strong>
course, and it is almost certain that whatever is written will meet with some vigorous
opposition! In this chapter A. P. French has undertaken this difficulttask and written a
personal comment on some general principles in the hope that it will provoke further
thought.
He begins by discussing the educational goals of a secondary-<strong>school</strong> <strong>physics</strong> course;
this leads to the selection of subject matter to realize those goals; finally he discusses the
role and the use of mathematics in such a course.
There are other important questions when considering the content of a course:
integration with other disciplines. the role of technology and the part that the history of
science might play in such a course. These issues have been intentionally omitted from
this chapter and are discussed separately and in detail elsewhere in this volume.
6.1 Introductory remarks
If one tries to come to grips with the problem of syllabus or course content in
<strong>physics</strong>, one’s dogmatic instincts tend to fade away. There are various reasons for
this but prominent amongst them is the certainty that no uniquely correct solution
to the problem exists. Probably the most that one can say is something to the
following effect: ‘ Here is a set of topics that make good sense to me and seem to
hang together in a reasonable structure. I believe that they direct attention to
some of the important principles of the subject. I could guarantee to talk about
them with a sense of enthusiasm and purpose. and I believe that my pupils would
absorb some of my enthusiasm and acquire some worthwhile knowledge and
understanding of the physical world in the process.’
This kind of subjective approach need not be disturbing. The quest for absolutes
can too easily lead to a rigidity that is both misleading and sterile, and a
thoroughly healthy attitude is perhaps expressed in the old saying: ‘It is better to
travel hopefully than to arrive.’ For if ever the time should come when pedagogues
agreed on what constituted the right syllabus, the spirit of fresh and
critical reappraisal would be lost. Fortunately the probability of any such general
agreement seems almost negligible in the academic world; one can happily urge
one’s own prejudices without any fear that they wil gain general acceptance.
85 Introductory Remarks

Another reason for diffidence in discussing the content of <strong>physics</strong> courses is
the awareness of how much wisdom and effort has gone into these matters in
different countries and over a long span of past time. At every stage one finds
evidence of immense care and thought devoted to curriculum planning. As excellent
examples, attention might be drawn to the monograph Science in Secondary
Schools (HMSO, 1960) (especially chapter 16 on ‘The teaching of <strong>physics</strong>’) and
the OECD (1965) publication <strong>Teaching</strong> Physics Today. The latter is rich in
details of course content and syllabus, and one article does venture to suggest a
rather specific selection of topics (‘ Essentials for a minimum course in <strong>physics</strong>’
by H. Schoene). However, although a concern with syllabus details is both legitimate
and necessary, it must always be seen as only one aspect of the total pedagogic
problem. Above all,the pupil as well as the teacher should have a sense of
why he or she is being asked to follow a particular route. Perhaps the most
admirable feature of courses like P S S C and Nuffield <strong>physics</strong> is their assiduous
attention to this problem.
6.2 Educational goals
The American author James Thurber in his Fables for Our Time has one story
(‘The Scotty who knew too much’) that ends with the moral: ‘It is better to ask
some of the questions than to know all the answers.’ This might well be taken as
the guiding principle of any field of intellectual endeavour, and especially of the
observational and experimental sciences. The element of rote learning is still too
much in evidence in many classrooms. The more detailed and rigid the syllabus,
the greater is the likelihood that an authoritarian atmosphere wil develop; yet
even a course aimed at fostering exploratory attitudes can founder on the rocks
of an autocratic tradition, or be frustrated in the hands of a teacher who is unwilling
or unable to operate in a loosely-knit structure.
The longer one teaches the stronger is likely to become one’s conviction that
the attitude to <strong>physics</strong> presented in a course counts for far more than any particular
choice of subject-matter. One still sees far too many examples of <strong>physics</strong>
being presented as a well-defined body of knowledge that is true for all time.
Such an approach failsto communicate the fact that <strong>physics</strong> is a growing subject,
living on imperfect data and provisional theories, and constantly being changed
and developed in the light of new observational evidence. One of the most important
things we can do is to make students aware that no theory has ever survived
without alteration or replacement.
There is admittedly a big problem here. Every teacher feels that there is a certain
large body of facts and formulae that a student should be introduced to.
(The fact that different teachers disagree on the content of this list is another
matter.) There is the temptation to be as efficient as possible in presenting this
material in streamlined form. This temptation should be resisted. In trying to be
efficient we may destroy the whole feeling for what doing <strong>physics</strong> is like. And what
a student wil chiefly remember in later years is the attitude with which it is presented,
not the particular facts.
86 What to Teach : Some General Principles

If one had to identify a special villain in the piece, it would probably be the
textbook. It is essential that text<strong>books</strong>, which do so much to dictate the character
of a course, should be written in such a way as to encourage independence of
thought on the part of the reader, so that he feels free to question any statement
and is encouraged to test it, wherever possible, in the light of his own knowledge
and experience. There is a sense of finality, and even of sanctity, in printed
words, far transcending the intentions of their fallible human authors. Indeed
students have difficulty in associating a textbook with real human <strong>source</strong>s at all ;
in extreme cases the book assumes a status comparable to the engraved tablets of
the law that Moses brought down from Sinai. Anyone who has himself written a
book and has also taught from it in a class wil have experienced the curious
phenomenon of a student coming up with a question. pointing to a place in the
book and saying, ‘He says here that. . . .’ There seems to be no awareness that
‘ he’ is the flesh-and-blood person standing before him.
This point is stressed because it means that everyone ~ author, teacher and
pupil alike ~ must make the effort to cast the textbook in its proper role as a servant
and not as a master. In other words one is concerned not with the book as
such, but with what it conveys. It should be written in such a way as to elicit and
provoke questioning; it should not confront the pupil with an array of unsupported
assertions. It should present the reader with real experimental data, complete
with errors. It should. where possible, quote from the original literature as
written by pioneering scientists. It should, in short, be as different as possible
from the traditional, tightly-knit, self-contained manual of instruction. Perhaps,
if its role can be fulfilled in other ways, it should not even exist. (The Nuffield
programme will help to show us if this is feasible.)
The proposition being made here (not of course a new one) is that the essence
of a successful course in <strong>physics</strong> is not the syllabus, not the textbook, not the
examining board, but what goes on in the individual classroom. Books, experiments,
films,examinations, etc., provide the raw instruments, but the teacher
and his pupils should be the conductor and the players who orchestrate them
and make them into a living experience. We who worry about curriculum
development and about the goals of <strong>physics</strong> courses, should keep that fundamental
truth in mind as we grapple with the more specific questions of course content
and method.
6.3 The selection of subject matter
What about the real business of constructing a list of things that every <strong>physics</strong>
student ought to know?
As I have tried to indicate earlier, my position is one of being biased but not
dogmatic. For example, I believe that the trend to include some atomic <strong>physics</strong>
at the expense of some of the classical mechanics is a healthy one, and indeed
essential. On the other hand I do not believe that this is a magic recipe for arousing
excitement and interest where it did not exist before. Atomic <strong>physics</strong> can be
presented as though it were a seed catalogue, and classical mechanics can be
87 The Selection of Subject Matter

made enthralling in the hands of a teacher who loves and understands it.
Nevertheless the choice of subject-matter does count and I would argue as a
general principle that it should be based, as nearly as possible, on the array of
fundamental facts and ideas in terms of which the practising physicist describes
the world. This means amongst other things an acceptance of the dominant position
that quantum <strong>physics</strong> occupies in our understanding of the structure of
matter. To a lesser degree it should involve some recognition of the modification
in our world-view brought about by relativity theory. However, there is another
aspect of the situation on which our courses and syllabuses are extremely vulnerable:
this is the matter of not seeing the forest for the trees. Letme discuss this in
more detail.
We are still very much the heirs of the first great flowering of man’s discovery
of the physical world and the organization of this knowledge in terms of different
categories. Even now it is more than just a convenience to regard sound and heat
as areas of study distinct from particle dynamics, or optics as separate from
electricity and magnetism. For the <strong>school</strong>child beginning his own first exploration
of nature it is probably essential that he recapitulate to some extent this
diversity of experiences and phenomena. But it should surely be a major concern
of a <strong>physics</strong> course for seventeen-year olds to show how wonderfully economical
nature is, how few basic principles are actually involved, and how they serve to
unify our picture of the physical world.
Those who have read Volume I1 of the Feynman lectures (Feynman, Leighton
and Sands, 1964) will recall that at one point he presents a table with the bold
title ‘Classical Physics’. It occupies only half a page and consists of just eight
equations. These are Newton’s second law, the Newtonian law of gravitation, the
set of four Maxwell equations, the Lorentz force law and the law of conservation
of charge. One would never give this list to a student and say, ‘There it all is; the
rest is up to you.’ But one should certainly keep before him the idea that what he is
studying at any given moment is like a piece of a jigsaw puzzle; it may possess
interesting details in its own right, but it takes on a far greater value and beauty
when seen as a part of the total picture. There is no easy way to achieve this purpose,
but there are two steps in the right direction.
(a) One possibility is simply to reduce the sheer diversity of topics discussed or
listed in the syllabus. Eric Rogers was perhaps the first teacher courageous
enough to do this with his famous ‘block-and-gap’ course at Princeton University.
He showed us how a thorough discussion of a few topics made for an incomparably
richer educational experience than an encyclopaedic survey course,
which in the worst cases might degenerate into little more than name-dropping.
The PS SC course has followed much the same approach, though less drastically.
Its complete omission of sound and its near-suppression of heat as distinct areas
of subject-matter is probably a valid response to the peculiarly American problem
of having only one year for certain in which to concentrate on <strong>physics</strong> in the
secondary <strong>school</strong>.
88 What to Teach: Some General Principles

(b) The second way in which we can help the pupil to see what is going on is to be
much more explicit about what is fundamental and what is merely incidental or
derivative. Two examples of this are discussed below.
6.3.1 Electromuynetism
The treatment of electroi?znyizetisni is often particularly deficient in this regard.
The teaching of electricity, at least in the older British tradition, moves far too
quickly away from the basic <strong>physics</strong> into a concern with devices and circuits.
A pupil could scarcely be blamed if he got the idea that a Wheatstone bridge is as
important as Coulomb’s law, and that is a bad situation. The fact is that the study
of electromagnetism is usually the pupil’s first real encounter with the subtle and
abstract concept of a field; this is further removed from his direct experience than
anything he encounters in mechanics, and it needs to be developed with great
care and patience. Why do physicists choose to analyse the interactions between
electric charges in terms of$eZds, when they have worked happily with forces to
describe the mechanical interactions between neutral objects? It is a question
that pupils should ask and to which they are entitled to receive a detailed and
thoughtful answer in the structure of their courses. This does not mean that every
pupil should be regarded as a prospective theoretical physicist, and in any case
the connection with real systems should be used to close the ring after an excursion
into more abstract considerations. But the few main ideas of electromagnetic
theory, on which one can build so much, are seldom given the prominence that
they deserve. And similar objections can perhaps also be made to the more
traditional presentations of other areas of <strong>physics</strong>.
6.3.2 Mechanics
When it comes to mechanics. we tend to run into a quite different kind of problem,
engendered by the long-standing tradition that mechanics should be taught
primarily as a separate subject, applied mathematics. As one who grew up and
flourished in this scheme of things I have since come to have strong feelings about
it. I regard it as an unwholesome anachronism that should be eliminated in the
teaching of mechanics at the secondary and even at the undergraduate level. My
objections are several.
First, it tends to divorce mechanics from <strong>physics</strong> in a pupil’s mind. He sees it
as a subject with certain basic rules, more or less arbitrarily supplied. The fact
that these rules are abstractions or approximations based on real experience is
quickly brushed aside. What remains is only an elaborate game of deductions and
manipulations. It is fun for those who happen to be adept at it, but it is neither
<strong>physics</strong> nor mathematics: it is a sterile anomaly, like a mule. When Newton
created the science of dynamics, it was a whole theory of the universe; he would
turn in his grave if he could see what it had become for generations of pupils in
secondary <strong>school</strong>s.
89 The Selection of Subject Matter

Some of my other objections are linked closely to the first. If mechanics is
taught as mathematics, the pupil is likely to see almost nothing of the real richness
and physical importance of the subject. A fair fraction of his time goes into
solving problems in statics. Most of the rest is devoted to deducing motions from
given forces. The way in which these forces arise, in any real system, from the
basic laws of physical interaction is almost ignored. Moreover the physicist’s
most basic exploitation of Newton’s law, inferring the law of force from the
observed motion rather than vice versa, is likely to receive no attention at all.
My last specific objection to applied-mathematics courses is the whole question
of emphasis in cases where pupils are taking <strong>physics</strong> and applied mathematics as
subjects of equal weight. My contention is that if these are both seen as disciplines
through which the pupil learns to analyse the physical world then the total
time that they represent should be combined and reallocated in a more enlightened
way. To have analytical mechanics equated- in importance to all’ the
rest of <strong>physics</strong> is an absurdity which becomes very apparent if one looks at the
superstructure of artificial and complicated problems that are the standard fare
in applied-mathematics examinations.
One last salvo on the teaching of mechanics, even within the framework of an
actual <strong>physics</strong> course. More often than not the mechanics comes at the beginning
of the course and, again more often than not, it is heavily tinged with the old
deductive, analytical approach. Many pupils, perhaps most, enjoy this appearance
of rigour, but it can be insidious for it tends to instil the belief that all of
<strong>physics</strong> is just a matter of carrying out orderly calculations on the basis of exact
premises. I wonder if we should allow such a view to gain an early foothold when
the true picture of how physicists learn about the world is so ‘different. Of course
the importance of intellectual discipline and logical deduction is not being challenged;
my concern is only that they should not be seen as representing the whole
story. Pupils should understand that the starting point is to look at nature, not at
a formula in a textbook.
6.3.3 A personal selection ofpreferred topics
Having said all this, where do I stand on an actual selection and sequence of
subject-matter? Quite apart from my doubts about the special merits of any one
choice there is the practical impossibility of suggesting any detailed programme
that would fit into educational structures as different as those of say the USA,
U K and the Federal Republic of Germany. It would in any case be presumptuous
to be too specific in view of the excellent work being carried on in individual
countries. My actual list of preferred topics wil therefore be brief and, I fear,
banal. Despite my strictures on the teaching of mechanics I feel that it has to
come early, since nearly everything else involves in some way the precise language
of forces and motions. But it ought to be preceded by something else. My other
concern would be to have the increases in abstraction and sophistication come in
a reasonably gentle fashion. Here then is a possible sequence of topics, though on
another day of the week it might have come out rather differently:
90 What to Teach : S ome General Principles

The physical world. Introduction to orders of magnitude; sizes and masses of
objects (nuclei to galaxies) (logarithmic scales); how lengths and times are
measured (a rich subject); the mathematical and graphical description of motion.
Mechanics. Types of forces ; forces in equilibrium; Newton’s laws, applications
of the second law; gravitation ; conservation of momentum and energy ; intimations
of Einstein.
Electromagnetism. Coulomb’s law; electric field and potential ; electric currents
and circuits ; magnetic fields of circuits; electromagnetic induction.
Vibrations and waoes. Natural vibrations of mechanical systems; forced vibrations
and resonance; vibrations of coupled pendulums; vibrations of long cords
and springs ; progressive mechanical waves (one-dimensional); waves on water,
reflection and refraction; interference and diffraction (mechanical waves) ;
simple theory of electromagnetic waves; polarization; optical interference and
diffraction ; geometrical optics (mostly in laboratory).
Quuntum <strong>physics</strong>. Evidence of discrete energy levels; particle properties of light;
wave properties of particles; standing waves and energy levels; energy levels of a
hydrogen-like atom ; structure of complex atoms.
Many-particle svstems. Kinetic theory of gases; introduction to statistical
mechanics ; structure of crystalline solids; mechanical properties of bulk matter;
specific heats of gases and solids.
A bare listing of topics. as above, cannot help being unsatisfactory. There is no
indication of the level or depth at which the topics might be discussed: this will
depend greatly on circumstances. Moreover it must be left to the reader’s imagination
or experience to decide how the individual topics may be fleshed out with
experiments. demonstrations, films,etc. Fortunately one knows that the educational
developments of the past decade or so have helped to strengthen the re<strong>source</strong>s
for this purpose to an impressive extent.
6.4 Mathematical content of a <strong>physics</strong> course
Every teacher knows that for very many pupils the difficulties that <strong>physics</strong> holds
for them are compounded by mathematical inhibitions. The belief is widespread
that one can. do little in <strong>physics</strong> without a set of high-powered mathematical
tools. This difficulty may loom much larger than it should. It can be greatly
eased if in teaching <strong>physics</strong> we pay particular attention to three main features.
These are: (a) the basic problem of transfer, (b) economy of techniques, (c) the
power of graphical and arithmetical techniques.
6.4.1 Transfer
By ‘transfer’ in this context is meant the ability of a pupil to take the pure mathematics
that he already knows and apply it in the context of a physical problem.
91 Mathematical Content of a Physics Course

This may entail difficulties for the pupil of such a primitive kind that it is easy for
an experienced person to overlook them. There is, for example, the fact that most
of the basic mathematics is done with an extremely limited repertoire of symbols,
mostly just x and y. For a beginner the use of entirely different symbols, for
example p and V in the gas laws, can operate as a significant obstacle. It may
sound far-fetched, but I have known of a case in which a pupil, perfectly capable
of calculating the area under the hyperbola xy = constant, was unable to recognize
that a calculation of the work done in isothermally compressing a gas, with
pV = constant, involved precisely the same mathematics.
The kind of difficulty mentioned above is aggravated by the question of the
dimensions of physical quantities. In <strong>physics</strong> we tend to be very casual and not
always clear about what we really mean when we introduce let us say the symbol x
to denote a displacement. Does x represent simply the numerical measure of distance
in some previously agreed system of units, or is it intended to incorporate
in some way the dimensionality of the quantity also? We almost always mean the
latter, but we rarely say so.
To illustrate this, consider an equation such as
x = t + t2 + t3
If x and t are just pure mathematical numbers, this equation is perfectly innocuous;
it is a clear and simple prescription for calculating the number x if the
number t is given. But to a physicist, reading x as distance and t as time, such an
equation is quite abhorrent. It suggests an equivalence between a distance and an
arbitrary admixture of seconds, seconds-squared and seconds-cubed. If a pupil
tries to read physical significance into this, he can legitimately object that it is
utterly confusing. We owe it to him to be scrupulous about introducing dimensional
constants so that the equation reads
x = At + BtZ + et3.
It then becomes clear how dimensional homogeneity may be guaranteed, or to
put it another way, how the numerical equality of the left-hand and right-hand
sides of the equation can be preserved in the face of any change of units of
measurement, thanks to appropriate changes in the values of the coefficients as
well as in the quantities x and t themselves.
Another aspect of the transfer problem, perhaps the most difficult of all, is that
of translation in the most literal sense, namely the operation of taking a plainlanguage
description of some relationship between different quantities and converting
it into an equivalent mathematical relationship between various symbols.
Although probably all pupils have some experience of word-problems in ordinary
mathematics, the task of using similar methods in connection with physical quantities
seems to be significantly more demanding and calls for special help and
encouragement. Perhaps this is because it involves in a very full sense the use of
mathematics as a second language. The pupil cannot take permanent refuge in
the symbols; he must stand ready to make translations in either direction between
92 What to Teach : S ome General Principles

the normal language and the mathematical one, and to interpret a symbolic
statement in terms of conceivable operations and measurements.
6.4.2 Economy ojtechniqiies
The wide variety of functions on which pupils sharpen their teeth in mathematics
tends to obscure the fact that an immense amount of <strong>physics</strong> involves the
use of very few basic functions indeed. To be provocative, I would suggest that
we can get along very well with only three kinds:
X" ;
e" (and log x) ;
sin x, cos x (with tan x and perhaps e'").
The simple power law, the exponential and the sinusoid really do cover an
amazingly large fraction of all the functional relationships that exist between
different physical quantities. Beyond this, special emphasis should be laid on
only one other mathematical concept, namely rate of change. This is so important
that even for pupils who have not yet had any calculus it ought to be introduced
in a more or less intuitive way, reinforced by purely arithmetical examples of
small differences involving particular functions. I think that we can perform a
great service to our pupils and to the cause of <strong>physics</strong> teaching by emphasizing
this economy of mathematical tools.
6.4.3 Graphical and arithmetical techniques
A last recommendation on the use of mathematics is in effect a plea for concreteness
through the use of graphs and arithmetic. Pupils are often eager to be
general and abstract. They should in my view be encouraged to see that this may
be unnecessary and even undesirable.
It is one thing to know that the quantitative relationship between two variables
is completely defined by a mathematical statement of the form y = f(x). It is
quite another thing to have a vivid picture of what this actually means, what
happens to y if x is doubled, and so on. The mathematical equation is in a sense
only the statement of a programme for finding y for any given value of x; it is a
point-by-point view. The use of a graph to display the whole course of the
relationship at a single glance is almost indescribably more powerful. (For this
invention alone Descartes should be acclaimed as a genius of the first order and
as a major contributor to the scientific method.) As every physicist knows, even a
crude freehand sketch of a functional relationship can be immensely informative,
and pupils should be encouraged to recognize and exploit this far more than they
usually do.
In a similar vein one might urge that every teacher stress the value of interpreting
a general formula in terms of particular numerical examples. Many pupils,
especially those who are strong and facile in mathematical manipulation, tend to
93 Mathematical Content of a Physics Course

look down on mere numbers. They are wrong. It takes practice and some conscious
effort to develop the habit of assessing, even quite crudely, the implications
of a given relationship and the relative importance of different terms in it. Consider,
for example, the problem of objects moving through liquids. Wil viscosity
or turbulence be the main <strong>source</strong> of resistance for an object of given speed and
linear dimensions? Such considerations are closely bound up with the whole rich
subject of the effects of changes of scale. A beautiful example of such analysis is
the well-known essay by J. B. S. Haldane, ‘On being the right size’ (reprinted
in Newman, 1956). By the use of such methods and ways of thought the pupil can
deepen his appreciation of physical phenomena and can greatly improve his
feeling for what the world is like and how it behaves.
6.4.4 Approximations
A final remark on this matter of being numerical and quantitative concerns the
use of approximations. Pupils are understandably suspicious and rather fearful
of them, for mere substitution in an exact formula requires no thought, but
approximation involves judgement ; it is an art that must be cautiously developed.
In very many cases, the hero of an approximate calculation is the binomial
theorem. All pupils learn this theorem, but how many of them fully appreciate its
power to yield useful approximate answers on the strength of its first two terms ?
How many, for example, think of it as a tool for obtaining a quite good value for
the hypotenuse of a right-angled triangle by the approximation
b2
(a2 + b2)* N a + -3
2a
where we assume b < a? (Even in the worst possible case, with b = a, the result
is wrong by only about 6 per cent, 1.5 instead of 1.414.)
Perhaps it is especially in connection with laboratory work and the estimation
of errors that this kind of use of the binomial theorem can be best developed.
Many teachers no doubt have their pupils apply the method to assess the fractional
uncertainties in areas, volumes, etc., associated with the error in measuring
a linear dimension. I would simply emphasize the wide usefulness of such
approximation techniques in theory as well as in practical work, so that, for
example, a pupil fully appreciates that the path of a falling pebble, even though
we say it is parabolic, is really a portion of an elliptic orbit and that the pebble is
during its brief flight an earth satellite of sorts. In such ways even the humble
approximation can help to enrich and unify different aspects of our description
of the physical world.
6.5 Laboratory work
There has been an omission in this chapter: almost nothing has been said about
the problem of laboratory work. This should not be taken as an indication of
indifference. On the contrary, the direct contact with phenomena and measure-
94 What to Teach : Some General Principles

ments should be regarded as being absolutely central. It has been discussed elsewhere
in this volume and in this chapter it has simply been taken for granted that
experimental work in a laboratory is an integral part of any course. The chapter
has been directed at the broader questions of the style, purpose and choice of
subject-matter. Given those, one would hope that their detailed expression in
classroom and laboratory experience would follow, and would be strongly influenced
by, the taste of the individual teacher and by his or her judgement in the
light of local circumstances.
6.6 Conclusion
In so far as the comments in this article come from a university teacher, removed
from the constraints and exigencies of the secondary-<strong>school</strong> classroom, they may
be subject to the charge of being unrealistic. It is easy to propound fine-sounding
principles when one does not have the responsibility for making them work. On
this point I will plead only that a long involvement with introductory <strong>physics</strong> at
the university level, coupled with a close association with many secondary-<strong>school</strong>
teachers, has helped to keep me within fairly close range of the <strong>school</strong> situation.
More importantly, however, setting aside some of the specific details, I would
be prepared to argue in favour of applying the same general attitude to instruction
at any level, be it elementary <strong>school</strong>, secondary <strong>school</strong> or university. In
essence it is a plea for intelligent flexibility, for a relaxation of the rigidity of
syllabus and structure. though with no compromise on intellectual discipline and
precision of thought. Of course rigidity is often just an unwelcome by-product of
large numbers. and here the problem of the secondary-<strong>school</strong> population is
orders of magnitude greater than that of an individual university. Nonetheless it
is my belief that further reforms at the secondary-<strong>school</strong> level are both possible
and necessary. Some of them cannot come about unless the stranglehold of a
detailed syllabus, prescribed from on high, is weakened or broken; the national
and regional examination boards have a heavy responsibility here. I would not
however put all the blame in that quarter. for I firmly believe that the teacher with
imagination and initiative can do great things within any given structure; much
of the rigidity within the <strong>school</strong>s is of their own making. These are very general
remarks, but I hope that the main text of this chapter wil have done something
to indicate how I envisage their application to the particular problem of <strong>physics</strong>
teaching in the secondary <strong>school</strong>.
95 Conclusion

7 What to Teach: The Problem
in Developing Countries
The previous chapter considered some general principles on the content of a <strong>physics</strong>
course. It was the academic approach of a professional physicist looking at his subject
and thinking what is relevant to the secondary-<strong>school</strong> pupil. It did perhaps reveal that all
is not yet well,even in the most highly developed countries, and how much further thought
needs to be given to curriculum reform. Much of the chapter is also relevant to pupils in
developing countries. Or is it?This chapter opens with a plea from Jerome Bruner that
developing countries should not attempt to follow slavishly what may be suitable for
pupils from a different cultural background. They may require something different, more
relevant to the livesof theirown pupils. This is followed by an interlude from Joseph
Elstgeest, which may perhaps have a useful moral, and the chapter continues with a
contribution from V. J. Long on the possible content of a course in a developing country.
Another personal view of the content of the course is then given by Fletcher Watson.
The chapter concludes with a light-hearted extract from the writings of Lewis Carroll.
7.1 A plea for an independent outlook*
The basic question is how you would expect to produce the kind of changes in
our educational system that would be commensurate with the task of development
in the new nations of the world. Let me first argue that if you try to imitate
the pattern of educational practice as it now exists in <strong>school</strong>s in technologically
advanced societies you wil be chasing after a chimera because there is no question
that our present educational system in ‘advanced’ countries is wildly in
transition.
Our present techniques of education represent a heritage from the Industrial
Revolution and, moreover, a response to a series of demands that have occurred
outside the educational system. For example, there was the requirement that
what we must do is to train apprentices; so vocational education of a kind got
started. There was the requirement that the sons of the rising mercantile dite in
England be polished up so that they could take their places in the general civil
service; so various forms of the moral science tripos, and so forth, were developed
at the universities. Then we started placing emphasis on certain kinds of topics
which presumably trained the general faculties of the mind; this meant basically
* This section, written by Jerome S. Bruner of Harvard University, is part of a lecture given at the
Rehovot Conference on Science and Education in Developing States, August 1969.
96 What to Teach : The Problem in Developing Countries

that you knew how to use your head but you did not know anything very specific.
There was then the further requirement that people take on the task of running
the economy of Great Britain. I am choosing England because it is a little easier
for an American to look across the water! So what happened was that Oxford
introduced the famous PPE course (Philosophy, Politics and Economics) and
that became an ideal. Then all the <strong>school</strong>s started producing a form of social
science that would prepare you for it, and examining boards started making
examinations to handle it. All these were responses to things that were taking
place outde the context of education.
When science education started in the United States with a new vigour in 1957,
it was not because suddenly our masters in the political sphere had the feeling
that the time had come to teach children to think elegantly about regularities in
nature. Not at all.It came about by virtue of the fact that we were terribly worried
that the Sputnik introduced a great gap, and that we were not keeping up in the
space race. There were other reasons too. but please remember that, generally
speaking, the dynamism for educational reform does not come from considerations
within the system, but from outside the system, and, I would argue, should
come from outside the system.
I would likevery much to urge a second point, and it is this. As you look at the
organization of modern states, you are struck by the fact that the concept of
bureaucracy is rapidly being replaced by the concept of the task force: rather
than having a continuing bureaucracy in charge of this or that segment of
society or technology. what you do is to form task forces that remain in being for
a certain number of years in charge of handling a specific problem that has
emerged within society. This turns out to be a response of a very deep kind to the
rate of change within society.
Classical Chinese culture invented bureaucracy and remained constant, or
relatively so, over millennia. As we move into a new period, I think new problems
come up all the time. They reflect the great issues that exist in society rather than
the questions that arise between the inspectorate and the <strong>school</strong> principals. This
leads me to think that education in developing areas ought to concern itself far
more with the problems that exist within developing countries, and far less with
the disciplinary ideas that grew up and reached their full flower in the great
German universities of the nineteenth century.
The notion may persist of organizing in terms yet again of chemistry, <strong>physics</strong>
and biology, which have been the glory and the bane of Western universities, and
of letting yourselves go through that again in your elementary <strong>school</strong>s and secondary
<strong>school</strong>s. I plead with you, think five times before letting that happen. Think
instead about certain kinds of ad hoc problems of your societies that have to do,
for example, with things like urbanism and what it means to live in cities. Organize
around concepts that are central to the local economy. If it is copper, then
organize the curriculum around copper; if it is soil, make it soil. But make it
specific and project-oriented, and make it temporary, not under the direction of a
ministry's educational bureaucracy but under a task force working for a five-year
period, and then set up another task force to take it from there.
97 A Plea for an Independent Outlook

Use the disciplines, to be sure, but do not let the disciplines dominate. I would
urge that in setting up a long-term perspective on education, and particularly
science and technical education in developing countries, it is utterly important
first to take objectives that have to do with the nature of the emerging society and
the goals desired; and secondly not to do it in perpetuity, not to set the structure
in such a way that it cannot change. Think about the task force, think about fiveyear
plans and a chance for correction after that.
7.2 The real problem
For the Rehovot Conference on Science and Education in Developing States, in
1969, Joseph Elstgeest of Morogoro Teachers College, Tanzania, recounted two
stories, writing as follows:
In the beginning of 1968 there was a rat plague in our neighbourhood. I happened to walk
through some of the fields surrounding a small village. The rain had been good, and the
people had planted maize, millet and rice.The men working in the fie!ds, friendly as ever,
stopped and stood to chat and to exchange the news of the day. But the news was not too
good: ‘The ratscome at night, after we have planted, and they dig up the seeds and eat
them!’
‘That is really bad! What are you doing about it?’
‘What can we do about it? Nothing. They come and they go during the night. We plant
again, and they come once more. It is a bad year for us.’
‘But is there nobody who has some idea?’
‘ Nobody.’
Some of the men suggested that perhaps the agriculture officer in town could do something
about it, but would he be a wonder-doctor? They thought that the idea of keeping
cats was a pretty good idea. ‘But who is going to give them to us?’
So they went on with theirwork. Ifthe rats eat their seeds again, they would plant again
in the same way, and hope forthe best, until either the rats or the seeds are finished. The
rats would probably win. . ..
This is a small, but typical example from rural Tanzania. It does illustratethe magnitude
of the problem this country is faced with: the problem of development beyond the level of
pure subsistence, beyond the struggle for pure survival.
The problem is not the ratsthat eatthe seeds; the big problem lies much deeper: here is a
situation which baffles the people, which defeats them; against which they have no weapon,
no re<strong>source</strong>. They feel defeated, and consequently they are defeated. It is a basic lack of
self-confidence.
One of the reasons for this sad stateof affairsis the educational system inherited from the
past. It needs a complete re-thinking of the educational approach, particularly science
education
Joseph Elstgeest’s second story recounts a conversation :
EDUCATOR What should you do with the drinking water in the village?
BOY Drinking water should be filtered and boiled.
EDUCATOR Why?
BOY Because it is unsafe to drink unpurified water. It carries the germs of sickness.
EDUCATOR Good. Do you filter and boilyour drinking water at home?
98 What to Teach: The Problem in Developing Countries

BOY No.
EDUCATOR But. . . don’t you get sick?
BOY No.
Many more examples could be cited, but this is not the place. The fact is that we have
made syllabuses and revised syllabuses, often in the comfort of an office.and not seriously
considered their effect. The fact is that we have always given answers to the children and
never real problems. When we did ask the children questions. it was with the intention that
they regurgitate the answers we had given them previously ~ ‘drinking water should be
filtered and boiled’. The fact is that we have never taught the children to ask questions, and
we have never given them the chance to rely on themselves to find the solutions: how to
prevent the rats taking the seeds.
We gave them answers and kept the confidence to ourselves. We gave them memory and
kept the thinking to ourselves. We gave them marks and kept the understanding to ourourselves.
This must change.
Perhaps the moral of this story by Joseph Elstgeest is that the content of a
course does not really matter as long as it is seen by the pupils to be relevant to
their environment. The important thing is to stimulate an inquiring mind and
through the pupils’ own experience to discover the richness of doing science,
rather than worrying about the facts; to make them aware of the value of science
education as a way of thinking and as a way to self-confidence. The foundations
for this wil certainly be laid in the primary <strong>school</strong>s, but secondary <strong>school</strong>s also
have a heavy responsibility, so with these reservations in mind let us now consider
what should be the context of the secondary-<strong>school</strong> <strong>physics</strong> course in a
developing country.
7.3 The content of the <strong>physics</strong> course
The choice of topics is influenced by a number of factors. First, and above all,
there are the needs of the pupils. Not so long ago science was regarded as a subject
for the specialist and the ordinary citizen cheerfully asserted that he did not
understand science. This has changed. The world we live in is so organized that a
citizen is ill-advised not to know something about how a scientist works, how he
checks his theories, how he tries to solve problems, how he becomes sure that
some things are impossible (perpetual motion, for example, or order out of
chaos). There wil also be the needs of the pupil when he has left <strong>school</strong> and
returned perhaps to his agricultural environment: he will need to know how to
recognize problems and how to set about finding solutions.
A second factor is the timing and staging necessary for growth of understanding.
To move too quickly to an abstraction, to introduce a concept which is new
to the pupil without an adequate lead-in to it, to overlook the need for stabilizing
periods between successive stages of sophistication, is to condemn a good part of
the class to despondency and a rejection of science.
A third factor is the link with studies outside <strong>physics</strong>. The ideas and thought
sequences of <strong>physics</strong> have been used with resounding success in all branches of
science, pure and applied. The needs of other branches must also be considered in
deciding the content.
99 The Content of the Physics Course

Finally there is the internal structure of the subject itself. Physics can be
described as a body of ideas for dealing with a wide variety of phenomena. Its
elegance comes from economy. The success of a single concept, for example
energy, in application to a diverse group of experiences is a major delight to the
scientist. A course should show something of this internal structure and not consist
of a sequence of isolated topics.
1.3.1 Assumptions
We will assume for purposes of this chapter that we are concerned with secondary
education, say from ages twelve to seventeen, before college or advanced course
stage. The pupils should have met some general science at a primary level,
though we wil assume that they have not studied <strong>physics</strong> as such. We wil hope
that they have some competence in arithmetic and that they will soon meet in
mathematics the formula and the concept of function. Once the stage we are considering
is passed some specialization is likely to occur, but within the age range
we have chosen we assume that all the pupils in the secondary <strong>school</strong> wil do
some <strong>physics</strong>. A programme for this stage must be found which wil be appropriate
both for the prospective scientist and the non-scientist. It will, of course,
probably be necessary to adopt different rates of progress according to the
general ability of the class.
1.3.2 Physics and chemistry
The two faces of physical science should both be studied by the secondary-<strong>school</strong>
scientist. There have been brave attempts to develop a single course to include
both without any separation. Experience suggests that first approaches to science
move casually to and fro between all branches of the subject; at this stage the
barriers we have chosen to erect mean nothing to the pupils. Much later on,
when the concepts and patterns of thought are well-established, the advanced
students find the relevance of chemistry in <strong>physics</strong> and of <strong>physics</strong> in chemistry
exciting and stimulating. These two stages we might call the primary and the
advanced secondary.
Between the two there is a phase when it is necessary to limit the field of experience
because the concepts are still fresh and strange. The experiments are
very carefully chosen to elucidate the ideas being fostered, and it is advisable,
probably necessary, that <strong>physics</strong> and chemistry should be studied mostly in isolation.
On one day, in one laboratory, we put together evidence from which comes
a theory of the undiminishing electric current. On the next day, in another place,
we concentrate on the action of oxygen on different substances, building up ideas
out of which wil grow a particulate interpretation of chemical action.
Sometimes even at this level the two courses overlap, as for example in electrolysis,
but the emphases are different. The physicist is puzzling over liquid
conductors in his circuits; the chemist is pondering about what is going on at
boundary layers. Provided that the two teachers are fully conversant each with
100 What to Teach: The Problem in Developing Countries

the other’s work, it could be an advantage to return to the subject a little later,
with a different guide and from a different. not contradictory but complementary,
viewpoint.
As a further example, both courses find the evidence of Brownian motion
essential. The physicist concentrates on the hammering and the speeds; he thinks
in terms of mechanics. But the chemist wonders what happens to the particles
when they collide. Certainly the two points of view converge splendidly later on
when the specific concepts are readily at call in the pupil’s mind. but there is this
intermediate stage when progress is firmer if made one step at a time.
1.3.3 The course in the eyes of thepupil
Most of our pupils wil at first value the subject only for its usefulness; for its
success in ‘explaining’ a large body of experience and the power it gives in controlling
nature, even if this is no more than replacing a fuse. As science teachers
we shall not neglect to show the methods of science or the elegance of <strong>physics</strong>,
but this will be done by allusion or by the sudden betrayal to the class of our own
delight. For the pupil it is relevance that wil be most significant.
Modes of thought must be developed from stimulating common experience or
topical excitements. Calorimetry, if it appeared at all, might arise out of such
questions as how much food a man needs to do a day’s work, or how much fuel a
car needs to go twenty kilometres. Electrical theory might come from the question
how I can get this lamp to light or this motor to turn. The ideas must be applied
as soon as possible to problems which the pupils see to be important: ‘ Can I get a
clearer view of the moon?’ or ‘What is the stopping distance of a car going at
60 m.p.h.?’
Dr Kothari of India writes :
The basic content of <strong>physics</strong> courses is almost the same in all countries. The order in which
various topics are presented may vary, as also the examples chosen to illustratethe different
principles. It is by choosing proper examples that one can link <strong>physics</strong> with the surroundings
and the daily life of the people, in other words make <strong>physics</strong> more relevant and exciting.
In most developing countries text<strong>books</strong> which were written in advanced countries are used
(either in their original form or in translation) and as such do not reveal the relevance of
<strong>physics</strong> to the average pupil. There is little doubt that these succeed in providing sound
knowledge of the basic principles to the pupils, yet they fail to develop in the child the
capacity to correlate the principles of <strong>physics</strong> with things that happen around him.
Work in India might start with questions about a potter’s wheel or why during
summer water is kept cool in earthen pots* or why the temperature of a room can
be lowered when using evaporative cooling from straw curtains.
In any country a good case can be made for relating <strong>physics</strong> to technology, but
a better case can be made in a developing country. Where their new freedom has
raised high hopes, the people, whether politicians or <strong>school</strong>boys, are eager to
control the powers that they have seen Europeans and North Americans using:
* Around 1775 AD ice was being made in central India by evaporative cooling during the winter months
and was stored underground to be used in the summer.
101 The Content of the Physics Course

the electricity supply, the lorries and tractors, the trains, cargo-boats and airliners,
the great roads and skyscrapers. They hanker for these and can become
impatient when served with triangle of forces or Boyle’s law.
There is a second, quite different reason. Many up-country pupils in agrarian
communities have not the background of mechanical know-how which urban
pupils wil have. Without experience of machines and toys they need much more
help in relating physical principles to real life. Dr Kothari stresses the same
point: the children in India have in their background hardly any activity which
may be termed scientific, partly owing to the very high cost of most mechanical
toys, kits, gadgets and so on.
In spite of all the strong arguments for linking <strong>physics</strong> in <strong>school</strong> with engineering
projects, this is not at all easy. Engineering problems, whether in rapid communication,
in dam-building, in the control of industrial processes and so on,
can be highly involved. Nonetheless a beginning can be made and the class will
always follow the teacher eagerly from the classroom to his car, to see how the
carburettor, the headlamps, the brakes or the springs illustrate what they have
been discussing.
All through the course the skilled teacher will use a practical situation to open
a new subject and then later to demonstrate the value of the line of thought. Problems
of hill-climbing, of the case for thatched roofs or metal ones, of the sun’s
radiation stored in forest growth or mountain lakes, are all natural talking points,
but more modern achievements can also be used simply in many ways. Something
can be said about the television tube, the pre-stressed concrete bridge or the
diesel engine. For this there is a need for simple, short, well-illustrated <strong>books</strong>, in
which pupils wil see their <strong>physics</strong> applied.
7.3.4 A variety of solutions
The above does not lead to a single answer about content. The PSSC and the
Nuffield Physics courses, both powerfully influenced by Rogers’ (1960) Physics
for the Znquiring Mind, have established one good pattern. Other solutions, intended
especially for developing countries, can be found and efforts to this end will
continue as long as <strong>physics</strong> teachers find their subject fascinating.
Thus a recent study by East African working parties has introduced a simple
investigation of structures and materials as a part of the secondary <strong>physics</strong> course.
This avoids the traditional applied mathematics, but deals with strength, stiffness,
ductility and toughness, all empirically, leading to thoughts on internal
stresses and then on how to select suitable materials and how to improve them.
The topic is weak in its links with other parts of <strong>physics</strong>, but it is admirable in
showing some kinds of elementary experimentation and methods of handling
results; it has immediate application in simple and complex buildings and other
constructions, even the internal and external skeletons of organisms. The work
proposed on structures and materials in the East African Science <strong>Teaching</strong>
Project is now in the trials stage and details cannot therefore be given yet; it
should be seen in its entirety when it has passed its test.
102 What to Teach: The Problem in Developing Countries

1.3.5 A personal choice
V. J. Long of the East African Science <strong>Teaching</strong> Project writes that his own
personal inclination would be to find a place in the <strong>physics</strong> course for the following
:
(a) A carefully developed study of energy, to include, at the right moment, the
nature of heat.
(b) An experimental study of motion and its causes leading to Galileo’s and
Newton’s ideas about force and mass.
(c) Sufficient acquaintance with wave motion for it to be used as a possible mode
for discussing radiant energy.
(d) The nature of electric currents, direct and alternating, based on an electron
theory.
(e) The evidence for, and the convenience of, a particulate theory of matter, with
particular reference to the nature of a gas and of a crystalline solid.
Such a course would draw on local material and phenomena. In East Africa
there are great variations in height of land above sea level, raising interesting
questions about atmospheric pressure; there are vast inland lakes and equally
vast areas of parched land; there are volcanic hot springs and a sun which is
precisely overhead. All these could contribute to the course.
All parts of the course would require that the theories were made to grow out of
experimental evidence gathered by the pupils rather than the teacher.
Once the claims of this method were accepted by the pupils, later in the course
there might be a report on some further advances in <strong>physics</strong>, using film and other
second-hand evidence, in particular a simplified account of atomic structure and
of nuclear energy. On the other hand Mr Long’s choice wouid restrict further
study of radiation to a warning that a wave theory may not of itself be adequate;
an exposition of photons may not be justifiable at such a stage.
As this suggested course is not only for specialists but for everyman, the customary
emphasis on precision measurement can be reduced, allowing this attention
only when the class sees that it would be rewarding. Most of the special
techniques, for example the use of the vernier scale, are of small value to most of
us; the highly accurate results are not yet impressive to our pupils or may be
falsely impressive.
Even the powerful weapons of mathematics, such as the exponential function,
must not yet be used centrally, although an apt aside to the more outstanding
pupils may not be amiss. It wil be possible to give those pupils who wil need
them the requisite skills at some other time. Nevertheless there should be some
discussion of the reliability of experimental results and of the variation in
measurements, for this is valuable for a citizen to appreciate.
Above all, by the time this secondary stage closes the pupils must see what they
have attained, how they have a new set of ways of thinking about the behaviour
of matter which they have already used to satisfying effect. They must not feel
103 The Content of the Physics Course

that they have been shown a splendid set of tools which only those who go on
with <strong>physics</strong> will have the chance of using.
For the sake of Everyman let the course end with a discussion which relates
<strong>physics</strong> to life and at the same time illustrates the power and limitations of
science. This could take the form of an honest appraisal of the re<strong>source</strong>s of some
part of the earth, probably of the country for which the course is written, not
forgetting the need for intelligent conservation.
1.3.6 Another personal choice
Fletcher Watson of Harvard University makes a strong plea that <strong>physics</strong> be
taught in a humanistic manner to replace the generally irrelevant manner in
which it has commonly been taught in the past. He writes as follows:
Physics may not have been duller or more remote than many other courses taught in the
secondary <strong>school</strong>. But in recent years our society has been changing, in part as a consequence
of fantastic technological accomplishments and a growing philosophical concern
about the dehumanized, code numbered, punch card and generally polluted world which
the applications of technology are producing. Pupils are aware of the mass media of destruction,
nuclear missiles, napalm, nerve gas and biotic warfare, and they see the scientist
as the sorcerer whose apprentice has made possible a multitude of dreadful destructive
devices. These pupils find much appeal in a philosophical orientation concerned with the
here and now, the self, happiness, peace and a respect for the dignity of all human beings.
The teaching of <strong>physics</strong> and of most sciences is caught in the pinchers between the revulsion
at an increasing technological and dehumanized world and the growing desire for peace
and personal dignity. If <strong>physics</strong> continues to be taught as only the handmaiden of technology,
then we would do well to have it as an optional course for a small number of boys
and a much smaller number of girls who, for personal reasons, choose to enrol.
This bleak picture of <strong>physics</strong> as a <strong>school</strong> subject is unhappily too near reality in most
<strong>school</strong>s, but it need not be that way. Science does not exist in a social vacuum, for the
scientists are creatures of their times, weaned on the Zeitgeist, who can ask only certain
types of questions and carry their investigations so far as their instruments permit. The
major contributions of scientistsappear not only in the form of technological potentialities,
but as ideas that have had powerful philosophical impact in the total culture. The growth
of the Renaissance was influenced by the thoughts of Copernicus, Galileo and Vesalius,
while the Age of Reason was strongly influenced by the scientificthoughts of many men,
perhaps best epitomized by Newton. Our current culture is struggling to absorb the concepts
of relativity, the quantum of energy, Heisenberg’s uncertainty principle and symmetry.
Biological ideas with major social impact would include evolution and genetics.
Myriads of other examples could illustrate how scientific thought has influenced the
general culture over many centuries. Because <strong>physics</strong>, including astronomy, has a recognizable
history of theoretical propositions developed during more than two-thousand years. it
is a particularly powerful vehicle for bringing to the attention of students the long-term
oneness of the culture. Not only can <strong>physics</strong> be taught in a humanistic manner, but it must
be taught in a humanistic manner to replace the desiccated, technological, dehumanized
and generally irrelevant manner in which it has been commonly taught.
Within a humanistic approach what <strong>physics</strong> should be taught? To aid in the inevitable
104 What to Teach: The Problem in Developing Countries

selection that must be made in the design of any course the two recommended major
criteria might be: importance and significance. By importance is meant those major ideas
which over the last two-thousand years have been significant not only within <strong>physics</strong> but
within the total culture.
With Aristotle one can begin examining our descriptions of motion both in the physical
terms of velocity and acceleration, and through the modes and materials of artists, poets
and writers.
Our changing descriptions of the nature of the universe. whether geocentric, heliocentric,
or centreless-but-ever-expanding, provide a potent means for dramatizing the consequences
of social preconceptions and the consequences of a given world-view. Certainly a
pupil’s concept of universal gravitation, one of the grandest propositions of science. would
be a keystone in any course.
Development of the concept of energy and theories of heat, including the second law of
thermodynamics, are worthy of thoughtful investigation.
Similarly, electrical experimentation and electrodynamic theory have through technological
applications dramatically altered man’s modes of living during the past hundred
years.
The evolution of a chemical-physical model of the atoms, and the current studies of
atomic nuclei, are having dominant effects upon our social as well as our intellectual
societies.
In any course the above are among the important concepts that would be essential. Significant
ideas are those that have been, and continue to be, shaping the world of scientific
investigation in recent and current years; surely therefore at a more advanced stage some
attention should be given to relativity, quantum mechanics, probability theory and nuclear
<strong>physics</strong>. as the thoughts and lives of students will be influenced by these.
The general topics just suggested by Fletcher Watson are among those that lie
at the centre of the <strong>physics</strong> programmes developed by the Nuffield team, the
Physical Science Study Committee and the Harvard Project Physics. They are
also included in V. J. Long’s personal choice. As might be expected, each course
wil have differing emphasis and selection but they treat all or most of these
topics. The Nuffield course relies heavily on individual work in the laboratory.
Harvard Project Physics emphasizes the scientific ideas in a broader cultural and
historical context. All stress the interrelation of observed phenomena and the
development of explanations. It wil be interesting to see the new programmes
coming from the developing countries.
7.4 Conclusion
This chapter began with a plea from Professor Bruner that developing countries
should not slavishly follow the content of courses designed for use in technologically
advanced countries and also a plea for flexibility, that the structure should
not be such that it cannot change. Perhaps we might end this chapter with an
extract from Sylvie and Bruno Concluded, written by the English author Lewis
Carroll, best known perhaps as the author of Alice in Wonderland. A discussion
is taking place.
105 Conclusion

‘Which of your teachers do you value the most highly, those whose words are easily
understood, or those who puzzle you at every turn?’
I felt obliged to admit that we generally admired most the teachers we couldn’t quite
understand.
‘Just so,’ said Mein Herr. ‘That’s the way it begins. Well, we were at that stage some
eighty years ago - or was it ninety? Our favourite teacher got more obscure every year; and
every year we admired him more, just as your Art-fanciers callmist the fairest feature in a
landscape, and admire a view with frantic delight when they can see nothing! Now I’lltell
you how it ended. It was <strong>physics</strong> that our idol lectured on. Well, his pupils couldn’t make
head or tail of it, but they got it all by heart; and when examination-time came, they wrote it
down; and the examiners said ‘Beautiful! What depth!’
‘But what good was it to the young men afterwards?’
‘Why, don’t you see?’ replied Mein Herr. ‘They became teachers in their turn, and they
said all these things over again; and their pupils wrote it all down; and the Examiners
accepted it; and nobody had the ghost of an idea what it all meant!’
‘And how did it end?’
‘It ended thisway. We woke up one fineday, and found there was no one in the place that
knew anything about <strong>physics</strong>. So we abolished it, teachers, classes, examiners and all.And
if any one wanted to learn anything about it, he had to make it out for himself; and after
another twenty years or so there were several men that really knew something about it.’
Following Professor Keohane, the editor of this volume has taken a liberty
with the text: Lewis Carroll referred to moral philosophy and not <strong>physics</strong>! But
the point is the same. The really interesting thing is that Lewis Carroll wrote this
in the nineteenth century. Even at that time he was implying that the content is
not the significant thing, but the manner in which it is taught. Professor Bruner
suggested that a task force might look at the content every five years and perhaps
Lewis Carroll gives us a clue to the only way in which future generations can go
on learning about <strong>physics</strong>.
106 What to Teach: The Problem in Developing Countries

Part Four
Physics and the Secondary
Curriculum

8 Integration
This edited chapter is based on contributions by R. J. Heller, V. Lawrence Parsegian,
M. Fiasca. F. R. McKim and Maurice J. Elwell. Science derives meaning when
considered in the context of man and his soclety : the teacher of <strong>physics</strong> cannot isolate
himself. his pupils orhis science, and for this reason there are many who think that <strong>physics</strong>
should not be considered in isolation from the other sciences. This chapter attempts to
bring together some of the reasons for advocating integration and to suggest ways in
which integration might be achieved. There is always a danger that such a discussion may
get lost in generalities and. for that reason, no apology is made for outlining in some
detail, in section 8.5, features of one integrated course which might prove a stimulus to
those developing their own programmes and at the same time wil serve as an example of
what is meant by integration.
8.1 Integration and coordination
It is necessary in this chapter to be clear as to what is meant by integration. We
shall use the term in the strict sense of bringing together several subjects in a
single course in which scientific concepts are approached uniformly in spirit and
method. Carefully planned cooperation among several disciplines is a reduced
form of integration, but this wil be referred to here as coordination.
Science education at the primary level is already integrated more often than
not and will not be considered here; but at higher levels the requirements of
specialization have usually reduced the possibilities of integration. At least this
is true for scientists and engineers, though important work has been done on produTing
integrated courses for non-science students at universities. At the secondary
level, coordination has often been attempted and more recently some partial
integration, <strong>physics</strong> with chemistry, chemistry with biology, geology with geography
and so on. But there are good reasons for a completely integrated secondary
science course, and these wil be considered below.
8.2 Reasons for integration
8.2.1 The nature of knowledge
Integration has a fundamental importance which derives from the very nature of
knowledge. Knowledge is indivisible, and it is only arbitrarily, for facility of
109 Reasons for Integration

study, that it has been segmented into separate subjects. Specialization grows out
of our preoccupation with efficiency: we want to know, and we want our pupils
to know, as much as possible, and this involves ruthless pruning of work other
than that which is appropriate for the topic being studied. This may be fine for
committed physicists but for children who are still savouring the ‘world around
them’ such selection and intensity would not seem to be in the best interests of
science as a whole.
8.2.2 The study of interdisciplinary subjects
Integration allows for the very natural introduction of intermediate or interdisciplinary
subjects such as astro<strong>physics</strong>, bio<strong>physics</strong>, biochemistry, microbiology,
enzymology, psychophysiology, and also the human and economic
sciences, which for too long have been dissociated from science teaching. The
division of the major traditional disciplines into strict compartments causes these
subjects to be neglected, and this is particularly unfortunate since research work
at the present time is especially intense in these areas, as illustrated by the number
of Nobel Prizes which have been awarded in chemistry and in medicine and
physiology, for example, for work using the techniques of <strong>physics</strong>. Unravelling
the structure of DNA required knowledge from a number of science disciplines :
chemistry, biochemistry, mathematics and crystallography.
8.2.3 Economic use oftime and re<strong>source</strong>s
In the teaching itself integration avoids repetition, which is wasteful in manpower
and uneconomic in its use of re<strong>source</strong>s. How unfortunate, and what a reflection
on our present teaching, is the case of the child asked to write on the electron, who
inquires whether it is a <strong>physics</strong> electron or a chemistry one!
Even where there are <strong>physics</strong>, chemistry and biology courses, perhaps well
coordinated, alongside each other, the demands of non-scientific disciplines are
often such that pupils cannot do all three, however much this is deplored by the
science department. Inevitably the pupil gets an unbalanced science education.
This does not arise when a <strong>school</strong> offers an integrated course: the child is no
longer forced into early specialization and the difficulty of having to make a
premature selection of two sciences from the three without enough evidence to
show which will suit him best.
8.2.4 Advantages to the teacher
Assuming that the teaching of the integrated course is undertaken by one teacher,
there are advantages in terms of increased contact with children. This allows
greater interest to be shown and developed, and better assessments to be made of
children’s reaction to the work in progress than when they are taught separate
sciences for shorter periods of time. Some of the point of an integrated course
would be lost, at least in the lower levels of secondary education, if the biology
110 Integration

were taught by a biologist, the chemistry by a chemist and the <strong>physics</strong> by a
physicist. The single teacher wil be the better able to see the cross-links in science
as they occur in the work, and he wil be the better able to stress analogies and
give due weight to the basic principles and the techniques and methods common
to the three disciplines.
There is also the advantage to the teacher himself, who may not have been
trained in all three disciplines and who finds enrichment in his own teaching from
the broader spectrum of science he now has to cover. A <strong>physics</strong> specialist involved
in an integrated course may find himself learning biology with little previous
knowledge. In the process he may well become disconcerted by the approach
found in standard text<strong>books</strong>, with new language and concepts too suddenly
introduced, frequently with little or no previous reference or derivation. Such experiences
often suggest a review of his own technique in introducing a new idea in
his own special field. The need for sharing experience where specialist teachers
are involved together in teaching an integrated course can lead to a new camaraderie
and awareness of colleagues’ problems.
Again and again the trials of integrated courses in various parts of the world
have confirmed the enthusiasm of teachers teaching outside their usual scientific
discipline. When teachers’ guides and pupils’ <strong>books</strong> are well devised, the apprehension
they naturally feel on embarking on such a course is quickly dispelled.
This is especially the case when the course is such that it reflects a shift in emphasis
from the teacher being an instructor to the teacher as a guide to children exploring
phenomena, gaining experience and beginning to think for themselves about
the need for explanations of the phenomena. In other words, integration can
show that the patterns of rational thinking are common to science and not merely
to the individual disciplines.
<strong>Teaching</strong> <strong>physics</strong> through an integrated course also allows for more ways of
tackling particular topics, ways which wil help to remove some of the artificiality
both of words and initial ideas, for example the use of anonymous ‘bodies’ in
mechanics. This is not to say that all such artificiality wil be removed, but more
relationships are possible with a higher chance of a natural, unforced introduction.
Physics did not originate in a vacuum but arose out of seeking explanations
for observed phenomena, and we should endeavour at all times to give as wide a
background of experience as we possibly can. Clerk Maxwell once wrote:
‘ Science appears to us with a very different aspect after we have found out that it
is not in lecture rooms only and by means of the electric light projected on a
screen that we may witness physical phenomena but that we may find illustrations
of the highest doctrines of science in games and gymnastics, in travelling by land
and by water, in storms of the air and of the sea and wherever there is matter in
motion.’ Integration gives an opportunity for <strong>physics</strong> to be seen in a wider, more
relevant context and is likely to persuade children that science is a humanistic
activity, not one that is isolated and remote from the world in which we live.
At higher levels of secondary education, some form of team teaching may well
be appropriate, at any rate in the initial stage of the development of such courses,
11 1 Reasons for Integration

though it is hoped that as far as possible a single teacher shall undertake the work
if the fundamental goal of showing the unity in science is to be realized.
8.2.5 Vocational advantages and the need for versatility
The diversity and complexity of modem industrial requirements are such that
breadth of knowledge and experience are increasingly desirable. To quote one
example, suppose a scientist suggests a method of automatic analysis of blood
samples which can be done at a rate of one a minute, a process normally taking
several hours for a sequence of tests by traditional methods. This could be so
advantageous to clinical laboratories in hospitals everywhere that it is decided to
go into commercial production. The development and production clearly require
a knowledge of chemistry and biochemistry; the method of analysis using a
colorimeter needs the knowledge of the physicist. An engineer must design the
pumping stage and the methods of carrying out automatically the process equivalent
to precipitation, filtration, distillation, etc. A knowledge of electronics is
needed to provide a permanent record of the analysis. Finally there is the problem
of the storage of information in hospitals and elsewhere, so that the computer
engineer is involved. No one person need know the full details of each stage, but a
large number of people, whether involved with development, production or
sales, will need the breadth of knowledge and the flexibility of mind to appreciate
the principles involved.
Vocational needs are less commonly considered in a book of this type, but
increasingly industry wil require men with this versatility of outlook. Very much
depends on the background inculcated at the secondary <strong>school</strong>, which has the
responsibility for providing suitable manpower for industry.
8.2.6 Relevance
One of the noticeable features in recent developments in <strong>physics</strong> has been the
attempt to give new courses a unity by making the various parts of the syllabus
relevant to each other. One of the new projects, for example, claims to give
internal relevance. ' By internal relevance we mean the connections between and
the interdependence of different parts of the subject. ... If the different themes in
the course can be seen to cohere and form a structure, then the intellectual
attractions of the study are reinforced and the tasks of learning and appreciating
the different sections are helped because the pupil can fit them into a pattern.'
In the teaching of light, for example, the desire for internal relevance has been
one of the reasons for the change in emphasis. The importance of geometrical
optics has declined, because it was felt that it had developed into a topic largely
on its own, having few connections with other parts of the subject. The importance
of physical optics, on the other hand, has increased. In this part of the work
the wave model of light has been stressed, and this enables the similarity and the
differences between light and other wave phenomena to be discussed.
Another illustration of the desire for internal relevance is the way in which
11 2 Integration

atomic ideas have increasingly permeated the syllabuses. ‘A course should be
able to introduce some of the key ideas in the understanding of the structure of
matter at the atomic level, in the understanding of macroscopic properties in
terms of atomic properties. . . .’ A <strong>school</strong> examination syllabus states, ‘In all
appropriate topics emphasis wil be placed upon interpretation of the phenomena
in terms of simple kinetic theory and of interatomic and intermolecular forces.’
This move towards internal relevance within <strong>school</strong> <strong>physics</strong> syllabuses has
resulted in the subject appearing much more unified, and much less a collection
of disconnected topics than formerly. But it is still possible for <strong>physics</strong> to be presented
with no very clear connections to the other subjects being studied simultaneously,
be they mathematics, chemistry or biology. The emphasis on internal
relevance within the <strong>physics</strong> syllabus makes the asking of a further question inevitable.
If the attractions of any study are reinforced and the tasks of learning
made easier when the different sections fit into a pattern, why must the pattern
stop at the edges of the <strong>school</strong> <strong>physics</strong> syllabus? Are there not sufficient links
between <strong>physics</strong> and other sciences to make further integration between different
subjects desirable?
The argument in favour of integration at <strong>school</strong> level is further enhanced by
looking at recent developments in chemistry syllabuses. The emphasis on the
accumulation of chemical facts has lessened, and an attempt has been made to
explain the facts, and even to predict new ones, by placing more stress on atomic
and molecular structure, interatomic and intermolecular forces, and energy
changes. These separate developments in <strong>physics</strong> and chemistry make it clear that
the structure of atoms and molecules. and the forces between them, are the themes
which should underlie new syllabuses in both subjects. But there is a further connection
between the subjects in that some topics are common to both. for example
the kinetic theory of gases, and radioactivity. For students who study only one of
the subjects, this overlap does not matter. For students who study both (and the
majority do), the overlap is unsatisfactory, even if the teaching of the two subjects
is clearly coordinated. Furthermore, whereas ideas about atoms and molecules
are often assumed at the beginning of chemistry courses, the evidence for the
ideas is systematically developed durin,q <strong>physics</strong> courses, a sequence which is
hardly ideal.
This desire for internal relevance has led to the integration of <strong>physics</strong> and
chemistry into physical science courses, such as the Nuffield A-level physical
science course. This course has three broad areas: mainly physical topics, mainly
chemical topics and bridging topics. In any course of this kind there wil inevitably
be topics. like electromagnetic induction, which are physical, and others,
like the chemistry of elements of a group, which are chemical. But there can also
be bridging topics, which within the Nuffield course include atomic structure ;
kinetic theory and phase equilibrium; interatomic and intermolecular forces ;
structure and properties of matter ; and electromagnetic radiation, in which
emission and absorption are studied as evidence for atomic and molecular structure.
It is the existence of these bridging topics which unifies the course and can
make physical science appear as a single discipline covering the broad field of
113 Reasons for Integration

inanimate matter just as biological science covers the broad field of living things.
But is internal relevance enough? Perhaps the approaches as well as the content
of courses should demonstrate more ‘relevance’ to life’sinterests if pupils are to
be attracted to include <strong>physics</strong> in their studies. This wider aspect of relevance is
considered in the next section.
8.3 What makes <strong>physics</strong> relevant to life?
Teachers of <strong>physics</strong> have no doubt whatever that the subject they teach is fundamental
among all other sciences, for what other science describes the forces and
energies that govern the physical processes of nature ? Pupils remain unimpressed,
however, especially when they know that the vast majority of people manage
very well without ever having analysed how blocks slide down planes or ladders
stand against walls. They only need to notice in addition the heavy emphasis on
solving numerical problems which characterizes most <strong>physics</strong> text<strong>books</strong> and they
will try to avoid <strong>physics</strong> courses altogether. As a consequence many fewer pupils
take courses in <strong>physics</strong> than might benefit from doing so. We could add that
many of us who chose <strong>physics</strong> for a career did so despite the dullness of secondary<strong>school</strong>
<strong>physics</strong>. This is lamentable, for <strong>physics</strong> is indeed the disciplinary medium
through which one learns and teaches many of the most fundamental concepts of
natural processes. Its absence in the education of teachers is to be deplored for
the negative attitude this generates and transmits to young people. The same
absence in the education of lawyers, anthropologists, government specialists,
economists and theologians is no less serious.
There are several reasons for the failure to attract and impress pupils. To begin
with, although <strong>physics</strong> deals with the pupil’s own world of moving objects,
rotating wheels, electrical currents and weights and measures, the usual approach
to these topics too often appears trivial and separated from ‘real’ issues, or too
difficult because of the mathematics involved.
For example, instruction in the three laws of Newtonian mechanics and gravitational
attraction is likely to involve the usual experiments with the push-pull
of objects and the timing of falling objects. These wil interest some pupils and
bore many others whose minds are less committed to mechanical gadgetry.
Despite its importance, the average pupil finds even the first law of Newton (that
an object continues at rest or in motion until subjected to external forces) trivial
and almost undeserving of attention. The second and third laws and gravitational
attraction become only equations that must be remembered to pass examinations.
How many teachers take the trouble to point out the great unknowns that
are represented in the principle of action at a distance? How many manage to
convey to the class the significance of the formulation of Newton’s laws in the
historical and philosophical and religious context of their times? It is when these
aspects are included that the pupil appreciates both the laws of mechanics and
the contributions they represented to the Age of Reason and to the mechanical
philosophy of the next few centuries. But unfortunately these aspects are rarely
taught, for the reason that teachers follow only the narrow instructional patterns
114 Integration

to which they themselves were subjected during their university years and which
most text<strong>books</strong> and examination procedures tend to continue.
The story is similar as one proceeds to the study of gases. probability and
statistical representation, energy conversions. measurement techniques. For
most of us the laws of thermodynamics become exciting only as their implications
are extended also to the dimensions of the cosmos and to the living world. When
the order-disorder implications of the entropy concept are extended to the realm
of living organisms, wherein the local change in entropy goes counter to the
general direction of change. the teacher opens the door to the domain of philosophic
speculation. When he refers to phenomena that require statistical analysis
he can raise broad questions on the inadequacy of deterministic approaches to
phenomena in the physical and biological and the socio-cultural world.
In the same way one may present electricity, atomic structure, or electromagnetic
features of light either within a severely narrow experimental scope or in the
broader context of the great unknowns that attend each property under study.
In other words, to be attractive and to achieve full bloom the study of <strong>physics</strong>
must go well beyond the experiments one manages with the hands. so as to
engage the mind in questions that are the mark of the intelligent student. The
unknowns, the apparent contradictions of science and the interfaces that relate
experiments in <strong>physics</strong> with other disciplines and with philosophic, social and
religious questions of the student, these are the features that make the presentation
of <strong>physics</strong> acceptable to the largest number. To demonstrate the 'relevance'
to life, therefore, one must integrate <strong>physics</strong> within a larger framework of disciplinary
and human interests.
8.4 Types of integrated course
The easiest type of course to achieve is the coordinated course based on carefully
planned cooperation between the content of the separate <strong>physics</strong>, chemistry and
biology courses. But, to achieve the aims outlined earlier in this chapter, closer
integration is to be preferred to mere cooperation.
One type of integrated course may be termed the 'main theme' structure. For
example, the main theme chosen might be light, which would be studied in all its
astronomical, biological, chemical and physical aspects. Other unifying themes
which cut across many science disciplines are energy. ecological systems, change,
classification, fundamental particles, interactions and equilibrium. Alternatively
a course can be devised using a number of main themes, for example a course
entitled ' energy-matter-life'. Or a course could be based on the techniques of the
scientist; classification, observation, deduction and induction, the use of models,
data gathering and analysis, approximations and generalizations.
Another interesting type of integrated course centres around real problems
which abound in urban and rural communities. This type has been developed by
the Portland Project in the USA. Fifteen-year-old children first survey community
problems through library research, invited speakers and visits to governmental
agencies. They study problems such as air, water, noise, heat and radia-
l 15
Types of Integrated Course

tion pollution as topics for further investigation. They also have at their disposal
a large number of laboratory experiments in which they learn to extract organic
and inorganic pollutants from the air and water, they learn to measure noise
levels in various living environments, they learn to measure radiation. An ecological
system is created, interfering agents are introduced and observations are
made to discern changes in the system. All findings are logged in record <strong>books</strong>,
together with research results from community and library re<strong>source</strong>s. At the conclusion
of these investigations they wil have learned a substantial amount of
subject matter and the techniques for collecting and analysing data, and will have
quite intimate familiarity with problems of the community and alternative solutions.
This kind of course structure can be extended to include other urban problems
such as traffic congestion, population density, urban geology and rural problems
centred around local agriculture, mining, water and energy re<strong>source</strong>s, and the
discriminate use of fertilizers and pesticides. Through such studies scientific
principles can be learned, but the advantage lies in the application of these principles
to real problems, thereby enhancing interest in the course.
This plan of organization can also be extended to world-wide problems such as
overpopulation. persistence of superstition. food production, conservation of
natural and human re<strong>source</strong>s. ocean-re<strong>source</strong>s utilization and world-health
problems. Similarly, if science education in the villages of developing countries is
related to the real-life problems of its inhabitants, able children may be induced
to remain to help in their solution.
For the academically more able a more sophisticated course may be desirable.
Such a course* has been developed in the United States called Introduction to
Natural Science and, although it was designed for college freshmen, the content
and approach are such that in the United States the same texts and approach are
being used in a number of secondary <strong>school</strong>s. The content of the course is outlined
in the next section. It provides evidence of what can be achieved and illustrates
the substantial advantages offered by integration.
8.5 A sample integrated science course
The filling of the relevance gap must reveal the progress of science within the context
of the progress of society and the questions that beset the thinking man.
Clearly, the new course could not be simply a sequence in <strong>physics</strong>, astronomy,
chemistry, biology or social science, although it requires topics from all these
disciplines. To be significant the topics require integration that reveals the
commonness or relatedness of basic concepts and reveals progression with respect
to the history of man and of ideas. It must disregard artificial disciplinary boundaries
in favour of a broader natural science.
* The texts, published in two parts (Parsegian, Meltzer, Luchins and Scott Kinerson, 1968, and Parsegian,
Monaghan, Shilling and Luchins, 1968), are described in Parsegian (1969). A Teacher’s Gurde
and a Laboratory Manual are available for each part.
11 6 Integration

For this reason the course begins by inquiring how we can identify the processes
by which earth and man arrived at their present state. There is evidence
that mountains erode to become plains, that beds of seas are sometimes pushed
up to become mountains. These seem to support the principles of uniformitarianism
that were proposed by Hutton in the eighteenth century, namely, that slow,
evolutionary processes of the kinds that we observe at the present time have been
more important in geological history than the influences of occasional convulsive
eruptions of volcanoes or sudden shifting of the earth. By utilizing radioactive
and other dating techniques. we gain the geologist’s sense of time counted in
terms of billions of years. This prepares the way for understanding evolutionary
processes of the living world.
A review follows of the accomplishments of the Sumerian, Babylonian, Egyptian
and-Greek thinkers who raised questions that have been with us ever since.
There was the coming of astronomy, or we should say that astrology gave ground
to astronomy. Astronomy is pursued experimentally, as was done by the ancients,
with the naked eye, and of course we come up with the same wrong answers that
they arrived at in the Ptolemaic model of the movement of heavenly bodies. The
approach does more than develop respect for the work of the ancients; it also
teaches that we cannot depend on observation alone to develop ideas on science.
W e learn next that astronomy and the geocentric theories of the universe became
so enmeshed in theology as to force thinkers like Galileo to disown truth before
religious authority. This is not the only case of unnecessary conflict between
science and religious authority.
Then came Newton and his laws of mechanics and of gravitational attraction,
with their emphasis on experimentation. These laws are used to solve problems
in mechanics, but even more important than problem solving is the awareness
that these represented the spirit of the Age of Reason when every effect had a
cause. So faithfully did nature seem to follow the principles of cause and effect
that it seemed proper to ask whether every man is totally subject to fixed laws of
nature, like the stone that moves only when it is pushed. Proceeding with the
study of measurement techniques, kinetic theory of gases, probability concepts
and thermodynamics, the new ideas chip away at the idea of foreordained fate
for nature and for man. This leads to discussion of how determinacy made room
for indeterminacy even before atomic science developed.
The experience of the project on which this course is based revealed many
advantages in the use of the concepts and the techniques associated with control
systems with feedback, in other words cybernetics. This theme extends the concept
of cause and effect to a larger sphere of human activity. The approach of
cybernetics is to look for the ititerrelutionships among the factors that bear on any
situation. whether the factors or situation are mechanical. electrical. biochemical,
behavioural, or involve iilformution. The action-reaction principle is extended to
feedback reactions that are often circuitous and delayed in time, and for that
reason the concepts are suitable for approaching real-life situations that may be
fairly complex.
With Newton we learned that a force F applied to a stone of mass M causes
117 A Sample Integrated Science Course

that stone to move in a well defined manner. But neither Newton nor the Age of
Reason tried to take into account the one who throws the stone, or the fact that if
he hurls the stone and it hits somebody there can be feedback. In other words, a
long chain of events precedes the throwing of that stone, and a long chain of
interrelated events may follow, as is the case with every real situation in nature.
A discussion follows on the simple harmonic motion of a mass suspended from
a spring, and how a little motion of the hand that holds the spring can either
reduce the amplitude of motion or cause the mass to fly away, depending on the
phase relationship of the hand motion to that of the mass. Analysis is made of the
collapse of the Tacoma Narrows bridge, control of room temperature, driving an
automobile, and many examples of systems are found that remain stable only
because there is negative feedback present which resists change, whereas positive
feedback may cause a bridge or the economic system of a nation to collapse, or the
faith and body of a man to go to dust. The pilot classes of the project using this
approach showed great enthusiasm for selecting and analysing a large variety of
religious experiences, socio-economic situations, production plant operations,
personal experiences and so on.
After introducing the concepts of cybernetics as part of the physical sciences,
the techniques are available for extensive use in the study of biochemical, neurological
control processes of the body and for the study of ecological systems. The
fact that systems under study could include human elements along with electromechanical
elements helped to remove the mental barriers that normally tend to
isolate the two areas. In fact when one has learned graphical representation of
‘ systems’ and situations, it becomes relatively easy to recognize interrelationships
that exist in any new situation whether one understands the terminology or
not.
Probability and statistical considerations are shown to be exceedingly important
in the affairs of men and of nature. We learn how difficult it is to make
dependable observations and measurements, and how much more difficult it is to
interpret correctly what is observed and measured. Even precise measurements
and accurate equations do not give an explanation of the reason for gravitational
attraction, the reason for the charge of the electron or the reason for the structure
of the atom that produced the light. We might note that while the solving of problems
must remain a primary device for teaching <strong>physics</strong>, in motivational value it
does not begin to compare with class discussions of the knowns and especially the
unknowns of <strong>physics</strong>. It is highly deceptive to teach <strong>physics</strong> as an ‘exact science’
with the implication of its having in general done remarkably well, even though it
offers few answers as to the ‘why’ and ‘how’ of gravitational attraction, atomic
structure, electromagnetic radiation and so on. When taught in proper perspective
the pupil is quick to realize that <strong>physics</strong> has regions of uncertainty and
‘interfaces’ with all the other aspects of his life, be it religion, philosophy or social
uncertainties. This realization is healthy.
Once a basis of classical <strong>physics</strong> is established, the course moves into the twentieth
century with a study of atomic and nuclear science. The work includes the
new radioactive atoms which make possible remarkable techniques for many
118 Integration

areas of research. Nuclear power leads to nuclear-power reactors. producing
electricity to feed into the nation's power lines, as well as the threat of world holocaust
that has come with the nuclear bomb. Time is devoted to atomic and
nuclear science because of the importance these have for technology. research
techniques, philosophy, and on the socio-economic and political health of the
world.
Towards the end of this stage of the course the processes are reviewed by which
the concepts studied came into being, how inductive and deductive processes and
intuition were involved. The physical-sciences portion of the course ends with an
inquiry on what society has gained or lost through scientific progress in the
course of these long centuries. There are questions involving government, religion
and education, as they relate to science, that go largely unanswered against
the uncertainties that persist as to what constitute values for science and for man.
The second part. called The Life Scieiices. revolves more directly around life
processes, and especially around man himself. It begins with an inquiry on the
characteristics of living organisms as we know them on earth. But when we inquire
what space scientists should look for as evidence of life on other planets it
becomes clear that our definitions of life are quite inadequate for that purpose.
Pilot-class experience showed that an immediate plunge into chemistry is not
attractive to students. In fact the chemistry has to be essentially 'buried' in
biological topics. This offered a severe challenge, since the approach to the life
sciences is essentially biochemical and physiological, but the course seems to
have succeeded in making the chemistry acceptable and adequate.
Presentation of the living cell in a descriptive manner is followed by a discussion
of the colloidal nature of living matter. Only then do we begin discussion of
covalent and ionic bonds in molecules, van der Waal's attractive forces, and the
hydrogen bond. The nature of chemical reactions, or equilibrium states, and of
oxidation reduction processes follows. There is then a deliberate break in the
chemistry sequence with work on the origin of life. in which there are presented
the old and the newest ideas on that subject. There follows work on photosynthesis,
on respiration processes and on transport of metabolites across cell membranes.
In this context, and occasionally in a philosophical vein. we note that we have
not really learned at what point an assembly of molecules passes from being only
a chemical compound to become a living organism. Nor can we, with poor understanding
of the M'IZJ) of the covalent bond between atoms or of the forces between
charged particles, do more than vainly guess at the basic causes for the origin of
life. In the new context we return to the second law of thermodynamics and the
concept that the trend of energy flow in the universe is toward maximum entropy,
a state in which equilibrium means utter disorder and incapacity to perform
work. It is especially interesting that within living organisms the changes are
not towards greater disorder but toward an ordering of the random carbon, oxygen,
hydrogen, and nitrogen atoms into highly organized molecular structures of
plant and tissue. That is, the direction of entropy cliariyr nithiti the pluiit is to
reduce entropy. Of course when the system includes the radiation energy from the
11 9 A Sample Integrated Science Course

sun, it is easily determined that the overall change is still an increase in entropy.
Nevertheless, it is tempting to ask which is the more philosophically challenging
law or concept of nature - the second law of thermodynamics that predicts disorder
and the ultimate degeneracy of energy, or the defiance of that law (if only
for a brief moment of life) by every blade of grass and by every living thing.
The body’s processes are amazingly complex. We are reminded that the properties
of a whole organism go beyond those of its parts. For example, from the
approximately twenty amino acids that make up living tissues one cannot predict
the new phenomena that come into play when they are assembled into proteins
and cells and into an organism called man. This becomes even more evident as we
move next into the neurological processes of the body. From a discussion of the
neural electrical discharge, we proceed to the neural functions in the control of
the body’s respiratory, circulatory, sensory and thinking processes. There is
some comparing (and contrasting) of the central nervous system, and especially
of the brain, with computer systems. These parts, and one later on perception.
memory. and learning processes, give to neurological phenomena the importance
they deserve both as advanced aspects of biological research and as bridges to
social sciences.
Protein synthesis, genetic processes and the role of DNA-RNA molecules
in replication of cells and of organisms come next. But not all of nature’s drives
are to replicate according to fixed patterns. Despite the amazing effectiveness of
the DNA and RNA molecules for preserving the pattern of a cell, the drive that
maintains life against environmental changes compromises somewhat in order to
continue life under changing environmental conditions. That is, the stability of
species we observe in nature and in replication of cells rides on an evolutionary
trend that moves towards ends unknown. Over and beyond replication of species
there is the requirement that two of a species, a male and a female, alike and yet
not alike, participate to produce progeny. Thus, the slow but continuing evolution
of species is assured. To what extent this and ‘chance encounters’ represent
fundamental principles of nature we must leave to philosophers to fathom.
The subject of ecological balances is then explored, how plants and animals,
including three billion people, find some form of ecological balance or adaptation
within this biosphere. How good is this balance? There are within the large ecological
systems very many sub-systems, species or organisms feeding on other
species or organisms and finding balance, growth, or near-extinction of their
populations depending on the nature of feedback and control influences. Again.
the subject is best analysed within the concepts of cybernetics. When we reach the
considerations involving civilized man there suddenly looms the threat of starvation
for vast numbers of people in the face of a population explosion.
The terrors for man do not wait for that starvation period, however; they are
with us now. For the greatest uncertainties and hazards with respect to the safety
and well-being of man are not those imposed by nature but those that are created
and imposed by man on man. For this reason the course gives some attention to
the environment of man and to man’s relationship with man.
The course concludes with questions that bring us face to face with intangibles
120 Integration

and with the question of the overall impact of science on society. What have we
gained from the progress of science over the last few thousand years '? What have
we lost? What place can we assign to human values, ethics. religious thought and
theology, nationalism, education, technology and to science itself? The reader
may ask: What do we hope to gain from a course that explores so many unanswerable
questions along with instruction in modern science ? With their
asking we hope to cultivate an open mind, a searching mind, even a creative
mind, along with a measure of humility. Science derives meaning when considered
in the context of man and of man's society.
121 A Sample Integrated Science Course

9 The History of Science and its
Place in a Physics Course
This edited chapter is based on contributions by Sanborn C. Brown, Donald Lindsay
and Stephen G. Brush, respectively a professional scientist, a historian and an expert in the
teaching of the history of science and technology. The chapter attempts to collect together
some of the cogent reasons forincluding more history of science in secondary-<strong>school</strong>
courses, and it warns of some of the pitfallsand discusses some of the ways in which the
work may be done.
Organizers of new programmes will need to make a definite decision on whether or not
they wish to include some history of science and the extent to which they wish to do so.
There is now one major course based on the historical approach, Harvard Project Physics,
and all concerned with new programmes wil be wise to study this in detail before coming
to a decision.
9.1 The need for change : the point of view of the professional scientist
The tremendous and rapid growth of science has resulted in a phenomenal involvement
of our culture with science, but there has not been a corresponding
acceptance of science as part of our culture. We are constantly confronted with
evidence that the world at large looks upon our field as one reserved for the narrow,
mathematically-endowed specialist, contributing only to our technological
surroundings, talking a special language of science and occasionally nowadays
honoured for the scientist’s intellectual achievement, which the public makes
little effort to understand.
Part of the trouble lies in a major misconception in the mind of the public
about what science is. The layman thinks of science most often in the context of
what might be called the ‘conquest of nature’, divorced from the framework of
concepts that have important impact on our thinking and beliefs. We often discover
that the non-scientist thinks of science in terms of just ‘facts’ derived from
empirical’investigations, or in terms of rigid laws and far-reaching, but inhuman,
generalization. It is probable that the reason for the public’s image of science in
general, and <strong>physics</strong> in particular, derives from the attitude of our <strong>school</strong>s. We
have tended to teach <strong>physics</strong> as a catalogue of facts presented iill the framework of
laws to be learned, of formulae to be brought out and problems to be solved, and
of routine laboratory exercises aimed at arriving at pre-determined answers.
122 The History of Science and its Place in a Physics Course

The professional scientist is aware that the growth of knowledge in science has
been so explosive that basic changes in educational philosophy have to be
accepted. He also realizes that these changes must be guided not only by the expansion
of knowledge, but by a real desire to make every educated man in the
coming generation appreciate that science is a basic element of our culture. The
non-scientist too must also learn to understand this. He must be made to realize
that both the scientist and the non-scientist have common goals and values. Trying
to move in this direction by teaching science through its historical development
and in terms of the scientists as people is clearly a valid method, because its
very fabric demonstrates man in his scientific environment. The practitioner of
science is a highly trained and highly skilled specialist in the tools of his trade, but,
to quote a great historian of science George Sarton, ‘The historian of science is a
humanist, a man deeply interested in all the humanities of science and. above, all
in the personalities of scientific investigators.’ (Sarton, 1952. p. vii.)
9.2 The need for change: the point of view of the professional historian
The view that the history of science is a worthwhile subject for study has developed
very slowly amongst historians, not least because of the difficulty in
teaching it. Too often the historian was ill-equipped with the necessary scientific
knowledge, but in the last twenty-five years there has been an increasing awareness
amongst them that the teaching has to be done and that it must be a joint
effort. How did this change come about?
Historians have begun to appreciate that once Origin of Species (1859), Das
Knpital(lS67) and the writings of Freud at the end of the nineteenth century had
been published and absorbed history could never be written in the same way
again. Darwin, Marx and Freud changed men’s ways of looking at life and behaviour
and could not be disregarded. In the same way historians have come to
realize that the revolution which started in the seventeenth century in science
could not be disregarded any more than economics, biology and psychology.
The scientific revolution which began in the seventeenth century did three
things of great importance:
(a) it destroyed old ideas of authority, both in the science of the ancient world
and the middle ages and. of greater immediate import. of the Christian Church;
(b) it led to a colossal secularization in every possible realm of ideas;
(c) it greatly increased the tempo of life. For two-thousand years the general
appearance of the world and the activities of men had varied astonishingly little.
Consequently men were not conscious of either progress or process in history.
After the scientific revolution change became so rapid that it could be seen with
the naked eye.
Historians could not neglect these factors, which had emerged as part of man’s
story. New perspectives were opened up in history and it became clear that the
scientific revolution of the seventeenth century and subsequent developments
were in line with other great episodes in human experience, for example the
123
The Need for Change: The Point of View of the Professional Historian

empires of Alexander the Great or of Rome, or even the unique contribution
made to humanity by the Jewish people in exile.
The scientific revolution created ultimately the modern technological state, a
new factor in history and one capable of such rapid growth and development that
it gradually took control of other sides of life, in much the same way that Christianity
in the Middle Ages permeated not merely religious aspects of life and
thought, but many other areas, for example painting and sculpture, architecture,
education, law and political science. So when historians today record the fact of
western civilisation being carried to Japan in the past hundred years, they no
longer mean Graeco-Roman philosophy and humanist ideals or the Christianizing
of Japan; they mean the introduction of science with the modes of thought
and the apparatus of civilization which began to change the face of the West from
the seventeenth century onwards.
Thus science has forced its way into history and it is essential that we should
find a way to teach its peculiar history.
9.3 The dangers
The history of science must go beyond names and dates and an important word
of warning comes from Professor Brush* :
Most science texts use what is basically a logical approach; the author first decides what
subject matter he wants to teach, and then figures out the best way to present the subject
from a modern viewpoint, without regard to the way the subject developed historically.
Sometimes the author may be aggressively and self-consciously antihistorical, but more
often he feelsan irresistibleurge to throw in a large number of names, dates and quotations,
which gives the pages a superficiallyhistorical appearance. Thus we are told that the laws of
classical mechanics were first presented by Isaac Newton in his Principiu in 1687 (with the
fairly strong implication that of course no one should ever attempt to learn them from
that book), that Ramer first determined the speed of light in 1676, that the definition of
chemical element was first given by Robert Boyle in 1661, that evolution was first proposed
by Darwin in 1859 and so forth. Presumably these pieces of information are intended to
liven up what is thought to be an otherwise dull subject. Unfortunately, most of them are
factually wrong (and can easily be proved to be so); but worse than that, even if they were
correct, they would not contribute anything towards an historical understanding of science.
The advocate of the logical method can say, quite rightly, that his students would be just as
competent in doing and applying science if he told them that Darwin proposed F = mu in
213 BC, and Boyle first determined the speed of lightin 1947, so why bother with history at
all? The historical method must go beyond names and dates if it is to be of any value.
9.4 The present position
In spite of the many obvious advantages of incorporating the methodology and
studies of the history of science in the introduction of children to the concept of
science, it is not a widely used technique. In the Unesco (1966) survey of <strong>physics</strong>
* This quotation and most of the text on pages 128, 129 and 130 is reprinted from Brush (1969) by permission
of the American Institute of Physics.
124 The History of Science and its Place in a Physics Course

teaching the curricula for secondary-<strong>school</strong> <strong>physics</strong> instruction in Czechoslovakia.
Federal Republic of Germany. France, USSR, United Kingdom and
USA were discussed in some detail, and in no case had the history of science
been introduced in sufficient depth to be noted as a subject for study. There
appear to be three reasons which serve to explain why the history of science has
not found its way into our standard secondary-<strong>school</strong> curricula. One of these is
that the discipline is a fairly new one and hence has not had time to be fully
developed as a classical method. Another is the difficulty of who is to teach it: the
historian or the scientist? The third is a very real feeling on the part of some
people that science is not a cultural study. Speaking to an International Conference
on Physics in General Education, in Rio de Janeiro, Brazil, the American
Nobel Laureate R. P. Feynman said (see Brown, Clarke and Tiomno, 1966):
There is a difference between a science and the humanities, and an attempt to mix the two
at too early an age is a danger and a destroyer of the true cultural value of science. . . . It is
impossible to teach appreciation of anything to young children; you can teach them only
what the thing really is and then hope that the intelligence will produce the appreciation.
Although this extreme point of view is not shared by most secondary-<strong>school</strong>
teachers, it represents a direction which opposes the introduction of science as a
cultural value, and hence the methodology of the history of science which capitalizes
upon the cultural and personal impact of the sciences.
Despite contributions to the teaching of the history of science in various universities
and colleges of higher education throughout the world, it remains true
that very little has been done at the secondary level since the Unesco survey referred
to above. The English Nuffield 0-level Physics course incorporated deliberately
one piece of historical work, but was not otherwise historically orientated.
There has however been one very notable exception to the above which has now
been published, namely Harvard Project Physics. There is already evidence from
it that the extreme view expressed by Professor Feynman may be proved wrong.
9.5 Educational merits of an historical approach
Since there appears to be some disagreement about the value of the historical
method for presenting secondary-<strong>school</strong> science, it would seem essential to consider
further the special educational merits of this approach when urging its
introduction into the curriculum of the secondary-<strong>school</strong> programme.
(a) One of the characteristics of modern science, which is often difficult to present
in a real and impelling fashion to secondary-<strong>school</strong> pupils, is its characteristic
of rapid change. Theories and ideas which were widely held only a few years
ago are now superseded and discarded, and yet <strong>physics</strong> as an exact science is
taught with mathematical precision, problems are solved with great accuracy and
experiments are carefully evaluated for limits of error. The discipline of the history
of science exposes young people to the vast chronicle of changing ideas,
changing concepts, new and sometimes radical theories, to which man has had to
adjust repeatedly throughout his intellectual history. The whole concept of the
125 Educational Merits of an Historical Approach

dynamic quality of science is an inherent theme in the historical approach, which
is often difficult, and sometimes impossible, to present in any other way than in
terms of man’s constant search for better explanations and truer models of the
behaviour of nature about him.
(b) By necessity, secondary-<strong>school</strong> education reflects a very partisan and nationalistic
framework for the developing mind of the child. He must learn a particular
language; the political history he is taught concentrates on his native land;
geography and civil structures are clearly biased to teach him his own place in his
own national home. The history of science is almost unique in presenting a body
of accumulated knowledge which has been discovered by mankind as a whole,
irrespective of religious, national or even temporal restrictions. In presenting the
development of science and the social changes which it has brought about, one
can present the total story of mankind as an inseparable part of the world around
him in a truly international framework. This is the type of education to which
every young person in the world today should be exposed.
Is there a hope that a true history of science could play its part in removing the
scourge of war by concentrating on progress and development rather than on
nationalist history, battles and wars ?
(c) There is a need for the future citizen to understand the modern world and its
problems. Historians in the past could talk leisurely about the Bronze Age, the
Iron Age, the Renaissance, the Reformation, the Industrial Revolution and so
on. But today we speak of an Atomic Age, a Cybernetic Age, a Space Age, a Bioengineering
Age and the significant thing is that they are all happening at once.
We must understand them if civilization is not to perish.
The history of science, properly told, could highlight and explain the two
simultaneous revolutions through which we are passing: the scientific and technological
revolution, and the revolution of rising expectations, which is the product
of the former. Modern frustrations and resentments come from confrontation
between scientifically and technologically advanced countries and the
scientifically and technologically under-privileged countries. If a man can go to
the moon, if we are so affluent that we have to rely on advertising agencies to
persuade us to buy what we neither need nor want, we should be able to solve the
urgent cry of under-privileged nations, who may recently have gained independence
and so-called freedom, for a removal of sickness, hunger and poverty. An
enlightened, humane history of science could remove from men’s minds the
obsession that science means the bomb and replace it by the belief that science
means the welfare of mankind. Such a history could at least show that the power
to provide a good life for all is in man’s hands. Has he the wil to do so? That is a
moral, not a historical or scientific question.
9.6 The use of biographies
We have already been warned above by Professor Brush of the danger of thinking
of the history of science as a series of names and dates. But the historical
126 The History of Science and its Place in a Physics Course

approach to science through the personalities and biographies of individual
scientists is a very fruitful technique, and here the availability of <strong>source</strong> material
in the native language of the pupils is improving. Many countries have produced
famous physicists whose lives and works have been written up at several different
levels of intellectual sophistication. Here pupils' <strong>books</strong>, written in their native
language, about scientists and scientific developments become the basic ingredients
for classroom and project material. There are also excellent bibliographies
which have been carefully prepared and are at a level to be useful both to pupils
and the non-specialist teacher.
One must remember that history does not have to be ancient, and it may be
that in the past there has been too much emphasis on Copernicus. Kepler and
Newton, and not enough on modem history. Contemporary newspaper and
magazine accounts of developments in plasma <strong>physics</strong>, the electron tube, the
transistor and nuclear energy are perhaps more exciting examples of the development
of intellectual ideas than astronomy. mechanics, or heat and light.
Biographies, of course, do not always have to be of very famous men. There
are many scientists who have not necessarily risen to the apex of international
fame whose work has been extensively recorded and who are in every way as
useful in terms of the development of their science for <strong>source</strong> material at the
secondary-schoo level as are the lives of those of great renown.
The biographical approach also allows the teacher to emphasize how much
the personalities of the scientists have guided development. This was very well
brought out by G. A. Boutry from France, speaking to an international conference
sponsored by the International Union of Pure and Applied Physics in
1963, when he said (Boutry, 1964):
One has to recognize that there are several types of scientificmind. Between the antithetic
and complementary Faraday and Maxwell a continuous spectrum of scientificintelligence
is spread out for us to examine. One must be reminded that scientists are men and men of
their times with their character and their temperaments, their heredity and upbringing,
their capacity for love and for strife. al playing a role. large and small, in the formation of
their scientificattitudes of thought: I have a suspicion that Volta in his brilliantdestruction
of Galvani's conclusion was motivated by a dislike for Galvani the man and Galvani the
philosopher. Hate also has some creative value. The dislike of Laplace for Fresnel is
another example. It hastened the success of the wave theory of light.
There is a comparative simplicity in the biographical approach. It is as valuable
to know something of the lives of great scientists as it is of the lives of statesmen,
warriors or artists. Such an approach can show the variety of types of scientific
mind, it can show that scientists are like other men in their humanity and failings;
how much progress came from cooperation; how much from jealousy and dislike;
how much scientific discovery is the result of brilliant guesswork or mere
accident. But there are two dangers in this :
(a) the history of any subject must be more than a string of biographies;
(b) it is historically unsound to pick out those figures who seem to us to anticipate
our modern world.
127 The Use of Biographies

It is therefore essential to go deeper, for example to understand older systems
which were overthrown and to understand contemporary thought through the
eyes of its defenders as well as of its attackers. We must have a picture of how
great thinkers operated on the margin of contemporary thought. It is sometimes
of almost equal importance to study where blind alleys were followed and why.
A. C. Joshi of India, speaking to the United Nations Conference on the Application
of Science and Technology for the Benefit of the Less Developed Areas, at
Geneva in 1963, emphasised the importance of courses in the history of science at
the secondary <strong>school</strong> level by saying (Joshi, 1963):
Students should be shown how scientificconcepts developed, what has hindered and what
has accelerated the pace of science, and what science has meant to civilization and the life of
man. Such courses should enable ordinary people to understand the conditions which have
stimulated the acquisition of scientific knowledge since ancient times. They can be expanded
to include the broad development of ideas, covering the cultural factors and movements
that have helped to release man from superstitious beliefs, as also the conditions that
have retarded the development of human knowledge and civilization.
Such an approach should do much to help produce citizens with the requisite
vision and breadth of knowledge.
9.7 Another danger warning
Once again a timely warning comes from Professor Brush:
Our experience in trying to use historical materials in Harvard Project Physics has shown
many times that most <strong>books</strong> on history of science are inadequate for the needs of <strong>physics</strong>
teaching: they do not reallycome to grips with the technical problems that are crucial even
in a secondary-<strong>school</strong> course, and they often perpetuate historical myths. Since secondary
<strong>source</strong>s are likely to be either unreliable or inadequate or both, the <strong>physics</strong> teacher is
thrown back to his own capacity to do original research in the history of science, orelse risk
being superficial or wrong in his use of history.
To illustrate this, let us consider a case history, the determination of the speed
of light. Almost any textbook in <strong>physics</strong> or history of science wil tell you the
speed of light was first found by Rsmer in 1676, by a method involving the times
of successive eclipses of the satellites of Jupiter. As the earth moves away from
Jupiter in its journey around the sun, light from Jupiter takes longer to reach us.
Divide the change in distance by the time difference and you have an estimate of
the speed of light! In this way, we learn from the <strong>books</strong>, Rsmer found that the
speed of light is about 2 x IO* m s-’, i.e. about two-thirds of the modern value.
This version of the story appears to have satisfied most writers of text<strong>books</strong>,
but it is not good enough for the secondary-<strong>school</strong> <strong>physics</strong> teacher. If he is trying
to present the historical development honestly, and if his students are reasonably
critical, the question wil inevitably come up: How did Rermer know the distance
travelled by the earth in its orbit around the sun? Apparently he did not, because
if you look at Rsmer’s paper, you find that while he estimates that it would take
light about twenty-two minutes to cross the diameter of the earth’s orbit, he does
128 The History of Science and its Place in a Physics Course

not state what distance that is, and in fact he does not give urzj) numerical value
for the speed of light! The closest he comes to estimating a speed is in a rather
obscurely written paragraph, indicating that if light took as long as a second to
traverse the earths diameter, then since between successive eclipses the earths
distance from Jupiter would have increased by 210 earth-diameters, the timedifference
would be about three and a half minutes, compared to a total time of
forty-two and a half hours for the earth to travel that distance. Since no timedifference
of this magnitude has been observed. light must move much faster than
this. Of course one can make various speculations and inferences about Romer’s
knowledge of actual distances and speeds from this hypothetical example (the
most generous estimate still comes out less than half of the modern value of the
speed of light) but the fact is that he made no explicit calculation of the absolute
numerical value of the speed of light in this paper.*
At about the same time that Rcrmer was determining the time it takes light to
travel the diameter of the earth’s orbit, two French astronomers, Richer and
Cassini, were making an observation that could be used to determine the length
of this diameter. This was the famous determination of the parallax of Mars,
famous at least in the history of astronomy, though it has not received much
recognition by historians of <strong>physics</strong>. Richer’s expedition to Cayenne (a French
colony in South America, near the equator) was one of the first major government-supported
research projects. By observing the celestial position of Mars
simultaneously from Paris and from Cayenne, Richer and Cassini could determine
the minimum distance from earth to Mars. From the Copernican theory of
the solar system it was possible to estimate the relative distances of all planets
from the sun; so as soon as one absolute distance in the system was determined.
all the rest could be calculated. It appears that the crucial step of dividing Richer
and Cassini’s distance by Romer’s time was first taken by Christian Huygens in
1678. It was Huygens, in any case, who first published the value equivalent to
2 x 10’ m s- which subsequently was almost universally attributed to Ramer.
What is the point of this story? It is certainly not of great significance to
secondary-<strong>school</strong> students to learn that it was Huygens, rather than Rcrmer who
first published a value for the speed of light, that value being in any case about 33
per cent smaller than the correct value. It is of some value for the <strong>physics</strong> teacher
to realize that he cannot trust secondary <strong>source</strong>s on matters of historical fact.
But an examination of the historical circumstances of the first determination of
the speed of light, not only the writings of Ramer and Huygens but also those of
other scientists at the time, can lead to an understanding of two important facts
about <strong>physics</strong>. First, the brilliant breakthroughs in <strong>physics</strong> which occurred in the
seventeenth century were greatly indebted to astronomy, because it was mainly in
the realm of planetary and celestial motions that one could observe simple
phenomena. It is well known that the solar system provided the crucial testing
ground for Newton’s mechanics and his law of gravity; this is one reason why a
unit on the sixteenth- and seventeenth-century revolution is an integral part of the
* An English version of Rnmer’s paper has been available since 1935 in Magie ( 19351
129 Another Danger Warning

Harvard Project Physics course. But it should also be emphasized that the first of
the fundamental physical constants, the speed of light, was estimated by astronomical
methods, including not only Rnmer’s observation of Jupiter’s satellites
but also the heliocentric system of Copernicus; and that system itself was constructed
from observations going back hundreds or thousands of years in the
past.
The second lesson is that scientists of earlier centuries did not define their problems
in the same way as we do now. The difference may be due simply to the fact
that they were not as far along the same path as we are, or it may be due to a fundamentally
different philosophical outlook. It is the failure to recognize this fact
that distorts much of the use of historical material in science teaching. W e
present a fact or theory in a logical framework, by today’s standards, and then
ask: who discovered it first? Thus we ask: who first determined the speed of
light ? W e insert the accepted (but mythical) answer, ‘ Ramer ’, and go on to the
next fact. But if we take the trouble to ask what problem seventeenth-century
scientists were themselves concerned with, we find that the numerical value of
the speed of light, though useful, was subsidiary to the much more fundamental
question: is it finite or infinite? Galileo had struggled unsuccessfully with this
question. Descartes had almost gone so far as to stake his entire philosophy on
the axiom that light travels instantaneously. Thus by seventeenth-century standards,
Rnmer’s demonstration that the propagation of light takes a finite time, a
qualitative discovery, was far more important than Huygens’ quantitative determination
of the actual speed. It is only because we gloss over or take for granted
the finiteness of the speed of light that we ignore Rumer’s real discovery and
instead give him credit for what he didnot do!
From a pedagogical viewpoint, of course, it makes no difference who gets the
‘credit’ for discovering what, but it does have some value to point out that the
finiteness of the speed of propagation is by no means trivially obvious.
A similar example from the same period is Boyle’s work on air pressure. Boyle
was not the first to find the quantitative relation between pressure and volume
(Boyle’s law) but what he did do was even more important: he established the
fact that air pressure exists and is strong enough to lift a column of mercury
76 cm. Thus ‘ nature’s abhorrence of a vacuum’ could be banished from <strong>physics</strong>
along with the rest of the animistic conceptions prevalent before Boyle’s time.
Boyle’s real discovery was a qualitative one. Since all of us have been taught long
ago that air exerts a force on every part of our bodies (really rather implausible if
you stop to think about it) we fail to see how great a discovery this was.
9.8 Implementation
The fact that many text<strong>books</strong> maintain myths means that the history of science
offers considerable avenues of creativity, for the teacher as well as the student, in
a way that is not always possible in other disciplines. There is scope for the
teacher to do at least some of the research himself, and this inevitably leads to
lively teaching.
130 The History of Science and its Place in a Physics Course

There is considerable scope also for partnership between the historian and the
scientist. The value of this interdisciplinary work is too obvious to need stressing,
The historian can do much to set the historical background, but he must also
understand what the scientist is trying to do. It is not essential to be a scientist
for this: the arts can be discussed and explained without being a practising
artist.
It is however essential for the scientist to realize his responsibility to explain to
laymen what he is doing. We should not forget Lord Rutherford’s remark ~ ‘If
the scientist cannot explain to the char-woman scrubbing the lab floor what he is
doing, he does not know what he is doing’ ~ a remark with perhaps more validity
than many scientists are willing to admit, but which rings true to teachers at all
levels, who discover so often that they only come to understanding when they
have to teach a particular topic. The problems are those of scientific jargon and,
especially, the language of mathematics, both of which have to be translated for
the layman, but there are encouraging signs that this can be done. for example
the brilliance of the explanations of details about space travel given to laymen
throughout the world, and one should not forget the impact of Watson’s book
The Double He1i.x.
In any case, the importance of communication is becoming apparent in other
ways: as we are already beginning to notice, even a rich society like the United
States wil not give unlimited funds to scientists to conduct basic research whose
results only the scientists themselves can understand. Physicists who want to
build bigger and more costly accelerators are recognizing that they must somehow
communicate better with the public in order to justify the fantastic expenses
of these machines.
On the question of how the science teacher should prepare himself to use an
historical approach, we are faced with the rather serious problem that there is no
simple way. certainly no easy way, in which the required information can be
learned at present. The reason is that what is really valuable in an historical
approach is a detailed account of the intellectual and personal factors which go
into the making of a scientific discovery, and this can rarely be obtained without
careful and time-consuming research based on primary <strong>source</strong>s. The best type of
course in the history of science for a science teacher is not a series of lectures
surveying several centuries, but a workshop-seminar in which each person investigates
one or two case histories in considerable detail. In any case the science
teacher who is willing to devote a limited amount of time to improving his historical
background would be well advised to pick a single scientist, or group of
scientists involved in the same discovery, and learn as much as possible about the
subject. He could then give one or two enthusiastic and well-informed lectures on
this discovery, which would be a welcome change of pace in a science course
which must be logically (non-historically) organized as a whole. (If the history
has to be third-hand or mythical it may be better to forget it altogether.)
A course of this type could certainly be organized with or without the cooperation
of historians of science. It does not even have to be called history of
science; many of the case histories could be chosen from current research for
131 Implementation

which documentation is available. The goal of the course would be to discover
how science really works by examining actual discoveries. It might well fill the
place of a course in ‘scientific method’ although the outcome might be to show
that there is no such thing as The Scientific Method as it is usually conceived.
Probably the most widely accepted myth about scientific method is that
scientists use the ‘ hypothetico-deductive’ method for working out the consequences
of their theories, and then test these consequences against experiment.
Of course it is true that conclusions are frequently deduced from hypotheses and
then compared with the results of experiment; the myth consists in the notion
that this comparison is done objectively and that the theory wil always be rejected
if it disagrees with experiment. This question cannot be adequately discussed
here, but perhaps we can suggest one way in which detailed examination of case
histories might induce a more sceptical attitude. Suppose one considers a number
of cases in which famous scientists have ‘falsified’ the data supporting their
theories. Perhaps one should say rectify rather than falsifv, since the data themselves
are not wrong, but rather they are too good. They agree so well with the
theory, in fact, that it is a real strain on one’s credulity (especially if one has any
familiarity with the experimental techniques involved) to believe they were
actually obtained in the form as reported. One suspects that the scientist must
have been guided by his theory in selecting and rounding off the experimental
results and in knowing which ones to reject as spurious fluctuations. One need
only mention a few such examples (all of which have been discussed critically by
historians of science) to show how damaging this phenomenon can be to the
myth that scientific theories are always tested by experiment: Galileo and uniformly
accelerated motion; Lavoisier and the conservation of mass in chemical
reactions; Dalton and the law of multiple proportions in chemical reactions;
Mendel and the laws of heredity. The first example is used in Harvard Project
Physics, where the students are asked to repeat Galileo’s experiment with apparatus
similar to that which he might have used, and to decide for themselves
whether his reported result is credible.
To end on an encouraging note, the re<strong>source</strong>s for achieving historical understanding
are rapidly improving. Not only are there more university courses and
<strong>books</strong> on history of science now than there used to be, but they are of much higher
quality. New secondary-<strong>school</strong> science texts, such as Harvard Project Physics,
provide a good basis for an historical approach to science teaching. More historians
have begun to dismantle the old myths and go back to original <strong>source</strong>s to
reconstruct accurate accounts of discoveries. The role of irrational or aesthetic
factors and metaphysical preconceptions in the acceptance or rejection of new
theories is being increasingly recognized. Many important works which were
previously inaccessible are being reprinted and/or translated so that they can
easily be studied. Scientific organizations have begun to recognize the importance
of preserving documentary material in archives for the use of future historians.
All of this activity is making it possible to understand the growth of
science in a much deeper way than ever before, and teachers of science should not
miss the opportunity to convey this new understanding to their pupils.
132 The History of Science and its Place in a Physics Course

9.9 Conclusion
To neglect the history of science in the secondary-<strong>school</strong> <strong>physics</strong> curriculum is to
turn one’s back on the most useful educational technique of teaching science as a
necessary ingredient in our cultural heritage. If science as a way of thinking is to
be instilled into the intellectual life of our children, so that science can take its
place as one of the truly international concepts about which all men can agree.
the sooner we teach it as part of our culture the better. The very best way of
accomplishing this is through not only the scientific, but also the personal
struggles of its historical figures, through the ebb and flow of its ideas and its concepts,
and through the hopes and fears it has raised and assuaged. And in the
development of our future leaders of society, the very best time to do this is at the
secondary-<strong>school</strong> level.
133 Conclusion

10 Physics and Technology
This volume is not concerned with technological and vocational training, but justas
there is a move towards the integration of <strong>physics</strong> with chemical and biological studies in
order that the processes of science shall be seen as a whole, so it is also desirable that the
‘pure’ sciences should not be divorced from the world of technology, especially at the
secondary-<strong>school</strong> stage. Technology is now so much a part of life that awareness of it
should be included in the education for life of all <strong>school</strong> children.
This edited chapter incorporates contributions from very many different <strong>source</strong>s:
from industrial scientists, J. Volger and G. Diemer, R. W. Sillars, J. Thomson and
M. Milbourn; from Japan, H. Ootuka; from the USSR, A. S. Akhmatov and
D. M. Tolstoi; from Israel, Meir Avigad; from the United Kingdom, Norman Booth,
John Lewis, and Geoffrey Harrison and his colleagues from the Schools Council Project
Technology. The editor rather than the contributors must accept responsibility for what is
contained in the chapter when it has had to be edited in this way; in fact some of the
opinions are contradictory, but they are included in the hope that the chapter as a whole
wil be a stimulus to further thought and development.
It opens with an account of the relationship between <strong>physics</strong> and engineering, which
leads to a discussion of the needs of industry and how they may affect <strong>physics</strong> education.
A criticism of the new programmes developed for <strong>physics</strong> teaching suggests where there
may be weaknesses in them. The importance of some applied <strong>physics</strong> to assist motivation
is discussed next and this is followed by a detailed account of how an awareness of
technology and applied science has been incorporated in the <strong>physics</strong> taught in <strong>school</strong>s in
the USSR. The chapter concludes with some account of recent work in the UK.
10.1 Physics and engineering
The boundaries between <strong>physics</strong> and engineering have never been rigid but have
shifted and contorted, on the whole changing so that engineering steadily claims a
stand on ground that <strong>physics</strong> covered before, while <strong>physics</strong> moves into new
regions of understanding. In fact there is no frontier between the two, just a
vaguely perceived junction which is often crossed and recrossed by men who start
from either side.*
Without drawing too sharp a line, we generally regard the physicist as the
natural philosopher, the contemplative man whose first interest is to understand,
and to express as precisely as possible, the way events happen and the way matter
* This section based on contributions from R. W. Sillars will be found more elaborated in Sillars (1960).
134 Physics and Technology

is made in the inanimate world; he is the man whose first thought is to study his
environment and to be able to describe what exists and to predict what wil happen
in the most exact terms he can find.
The engineer is rather the man of action, who wishes to understand cause and
effect so that he can arrange the effects as he wants them; his first aim is to alter
his environment so as to make it more agreeable to live in. to make something
which wil add to the convenience and comfort of his friends and himself.
The relation of <strong>physics</strong> to engineering has no parallel in that the principles of
engineering, mechanics, hydrodynamics, electromagnetism, stress analysis, heat
transfer, thermodynamics and so forth, are all principles which were first studied
as branches of natural philosophy and then taken as working rules for engineering.
Many engineeringdesign methods consist of physical principles and discoveries
codified into a form in which they can be grasped and used without absorbing
all the background which led to discovery and proof. It must be essentially a
common-sense codification, concerned less with accuracy, general validity and
logical unassailability than with the ease of grasping what is concerned. This was
true in Isaac Newton's day as now. That practically minded man was not prevented
from formulating his laws of motion by the question whether his definitions
of mass and of time were independent of one another or independent of his definition
of force; he had found a consistent set of rules which worked and could be
used by intelligent people.
That the major discoveries and laws of <strong>physics</strong> ultimately tend to become incorporated
in the rules of engineering cannot be doubted. One is reminded of the
reverence accorded by electrical engineers to such names as Faraday, Maxwell
and Kelvin, or by recalling that the discoveries of men who for the last two generations
have striven merely to understand the ultimate constitution of matter are
now the basis of our only serious effort to avert a famine of coal. by providing
nuclear power. The process is inevitable. This is far from saying that physical
research should aim first to gain control over our environment; that may be the
engineers' point of view. The physicists see that engineering is a convenient byproduct
of <strong>physics</strong>.
But it is not the only process: engineering practice has often provoked entry
into new realms of <strong>physics</strong>. The appearance of the steam engine in France stimulated
the highly original reflections of Sadi Carnot on the conversion of heat into
work, which, together with the careful observations of Joule, were later to form
the basis of modern thermodynamics in the hands of William Thomson, Clausius
and others. Again, the modern theoretical developments of fluid dynamics, the
theory of the lift of an aircraft for instance. did not precede the design of the first
successful aircraft; they followed it.
Physics has given to engineering such principles as those of mechanics, electromagnetism,
thermodynamics, nuclear energy and the study of the solid state, all
of which will provide problems in applied <strong>physics</strong> for large numbers of the coming
generation of physicists. The big advances in material benefits seem generally to
come as a bonus on the acquisition of knowledge. If we are tempted to direct ourselves
too consciously to utilitarian ends we may recall that those most practical
135 Physics and Engineering

ules of engineering, Newton’s laws, came from a contemplation of the motion in
the heavens, an occupation which in the seventeenth century could have been of
practical significance only to navigators, to the more pedantic clock makers, and
to those who cast horoscopes. It must still be true that the best guides to progress
come from the directions intuitively taken by inquiring minds.
This requirement for developing inquiring minds is reflected in a recent remark
by a prominent British industrialist, W. 0. Alexander, commenting on the new
Nuffield programmes: ‘If it has been fairly observed that Nuffield science trained
students are likely to be backward in knowledge (in the sense that they have
covered less ground than in traditional courses), but are forward in their ability
to think, then I welcome Nuffield <strong>physics</strong>.’
10.2 What industry needs
Since we all depend for our daily bread on the productive capacity of industry, it
is self-evident that as teachers we have a moral duty to serve industry. The case
has been put above for the need for developing inquiring minds, but what other
requirements are there?
James Killian, as President of MIT, stated that employers were looking for a
sound education in fundamentals and for analytical power; they were looking
less for specialized competence than for the versatility necessary to enable a man
to follow any one of a number of specialities; the most pressing need was for
scientists with imagination and trained creative power to make the discoveries
and generate new ideas. He also advocated a larger content of basic science in
training programmes to produce a new type of engineer more adaptable to changing
technology. From this it is clear that employers want men with the power to
deal with the technologies of tomorrow, not of today or yesterday, and the
foundations for this are laid at the secondary-<strong>school</strong> stage.
There is a unity in <strong>physics</strong> as a subject; applied <strong>physics</strong> stresses the object of the
work rather than the work itself, but it is very doubtful if there is in fact any real
difference in outlook between pure and applied <strong>physics</strong>. On the other hand, the
applied physicist and engineer wil have to make decisions and this ability to make
decisions also derives from initial training at <strong>school</strong>.
J. Thompson (1960) wrote:
Academic scientists seldom make mistakes, but when they do it is of little importance. Time
rectifiesthe error and only the reputation of the erring scientistsuffers. But a mistake made
by the industrial scientist may cost the nation millions without it ever being realized that a
mistake was made. The academic scientist is able to choose his subject and to set the limits
of the investigation. He is therefore a specialist in the true sense of the word. The industrial
scientist has to take the problem as he finds it with all its implications. He can. and often
does, break it down, but to do so he requires a much more generous understanding of basic
science. He is not a specialistalthough he may employ them. In respect of difficulty there is
no comparison between the two types of effort.
An inquiring mind, a good basic understanding of science on a wide front, the
ability to make decisions: what else is required? Another industrialist, M. Milbourn,
writes: ‘Initiative is another important attribute. It implies the ability to
136 Physics and Technology

see the existence of a problem, to formulate a line of attack, to ensure that work is
done correctly either by oneself or by others, and to report it clearly and expeditiously.’
The question of reporting clearly must not be overlooked and again much
depends on initial training at the secondary level. He continues (Milbourn, 1960) :
Reports written by young graduates are frequently of a lamentably low standard, the fault
being not so much incorrect use of language as the inability to convey a logical exposition.
with particular reference to reasons for the initiation of the work, its relationship to allied
investigations and theconclusions drawn from it. Clarity of thought seems to be lacking. as
well as clarity of expression, indicating that the course of study has not instilled logical
thinking, but has concentrated more on the acquisition of facts and knowledge.
Finally, we should remember that the young engineers and scientists whom we
educate are the future leaders of industry. Leadership requires not only good
technical knowledge and judgement, but also the personal qualities which will
inspire others. All this puts a heavy responsibility on those who develop new
curricula.
10.3 A criticism of new <strong>physics</strong>-teaching programmes
The new <strong>physics</strong>-teaching programmes, for example PSSC in the United States
and the Nuffield 0-level <strong>physics</strong> programme in the United Kingdom, have all
earnzd justified praise for the way they have made science a <strong>school</strong> topic suitable
for inquiring minds. It might be called ‘cryptic clue’ science. It is a splendid intellectual
exercise, disciplined by experimental observation. and consists of the following
processes: (a) the observation of phenomena, (b) the conscious search for
patterns in the phenomena observed, (c) the rationalization of the pattern into
the form of a general statement and (d) the accounting for the pattern.
The accounting for the pattern can be done at different levels with different
degrees of sophistication, but ultimately, in <strong>physics</strong>, it is done in terms of three
components. which may be represented in the form of an equilateral triangle.
The sides of the triangle are: (i) the nature of the particles of which matter is composed,
(ii) the forces between them and (iii) the laws of energy which have to be
obeyed in all transactions.
The sides of this triangle set out the boundaries of pure science. In general,
pure physicists do not operate on phenomena which cannot be seen to be contained
within this triangle.
Having ‘explained’ the pattern within the triangle, the explanation is now used
to assist us in the incorporation of more phenomena, the same process as Newton’s
gravitational work based on planetary motion being used for other phenomena.
also within the triangle. But it also allows us to create phenomena for
our own purposes and this is what is meant by ‘applied science’.
Applied science is a component of technology. but only a component. Thus
Newtonian rationalization of circular motion tells us what to do about traffic
going round bends, but there are certain choices between LI, Y and F, and the
137 A Criticism of New Physics-<strong>Teaching</strong> Programmes

grounds on which we make that choice wil not be within the triangle. Technology
involves decision making and has to take into account more than is contained
within the triangle. A sound <strong>school</strong> programme ought to take into account
other components in addition to science for the inquiring mind.
One of these components which ought to be an integral part of a science course
might be called science for action. This could perhaps be represented by a circular
area around the triangle: it would involve decision making, for example
deciding what the banking should be when traffic goes round the bend. Work in
the triangle will give an understanding of conduction, convection and radiation ;
work in the circle outside the triangle wil help in the decision where it is best to
put a convector heater in a room. To take another example, we may go through a
number of ways of determining focal lengths in a <strong>physics</strong> course. We do this in
order to widen the pattern of, or to give practice in the application of, the principles
of geometrical and/or physical optics. But suppose you actually needed to
measure focal lengths of converging lenses at a rate and with an accuracy not
usual in the classroom. You need a box into which you can slot the lens, turn a
dial to give coincidence or something, and then read off the focal length. What
goes into the box?
Every part of a <strong>physics</strong> course (every pattern) leads naturally to this kind of
treatment. By not taking our <strong>physics</strong> so far, by deliberately confining it to the
triangle, we reduce its educational value. Unfortunately operations purely within
the triangle are much simpler, indeed they become almost routine, but there are
now the stirrings of an attack on the more difficult area.
Another component might be called science for citizens, represented by the
region outside the circle. It raises the question of how we prepare people, in a
democracy, to be able to make the decisions they must. Political, social and
economic decisions often have scientific as well as other aspects. Conservation is
much talked about now. How should one present energy, for example, so that
the citizen understands and can follow the arguments or so that he can demand
that the arguments be put? Why is it that converting energy in fuel into electrical
energy and electrical energy into heat is inevitably wasteful? Why must he
strike a balance between unavoidable waste of useful energy and convenience
when making or influencing national and personal decisions?
In short, a science course ought to have a balance of all three components,
science for the inquiring mind, science for action and science for citizens. The
exact balance is a matter for judgement, taking into account the demands of the
society into which the pupils are moving and the aptitudes of those pupils. Certainly
‘science for all’ must have all three components and must not hide itself
cosily away in its triangle. Have some of the new programmes done this?
138 Physics and Technology

10.4 Motivation
Applied science and reference to technology can have a powerful motivational
effect on <strong>school</strong> children. There is seldom any problem with the able child, but
with the less able even one example of a physical law being applied in the technological
field can make the work appear relevant and stimulate interest.
Something can perhaps be learnt from those countries where elementary and
secondary <strong>school</strong>s have a coordinated curriculum in which vocational and
general education reinforce each other. Coordinated work can be of great importance
in preparing the pupil for a technological career: graduates of academic
secondary <strong>school</strong>s are often not willing to become skilled workers or technicians
and if they have to work in this field, lacking other possibilities, they feel frustrated.
Incorporating some pre-vocational and technical work with general education
gives some pupils the self-assurance they need through their practical work.
and this newly found self-assurance develops a powerful motivation to study and
to enlarge their knowledge, even in the field of general studies which do not seem
to have any connection with their training. Such education helps to give an idea
of, and to develop a taste and esteem for, practical work thereby disclosing
interests and aptitudes which assist in vocational guidance and facilitate future
vocational adjustment. This of course is one of the reasons for coordinating such
practical and academic work.
But such coordinated work can also have a profound effect on the pupil’s
academic work in the sciences. Meir Avigad of Israel quotes <strong>school</strong> principals as
saying that this applied work had brought about a revolution in some pupils’
attiludes towards <strong>school</strong>: ‘Pupils who had negative attitudes and who had frequently
absented themselves from <strong>school</strong> turned into pupils who attended <strong>school</strong>
regularly and took a positive attitude towards <strong>school</strong> work.’ And again: ‘Positive
influence has been felt especially in science subjects. Newly found self-confidence
and discovery of their own potentialities have led to improvement in their general
scholastic attainments and in their attitudes toward work and studies, for example
in their willingness and perseverance.’
Academic courses in secondary <strong>school</strong>s in the past have been too closely geared
to getting pupils into the universities with the most prestige. Applied science in
some courses certainly provides motivation. showing yet again how relating
<strong>school</strong> work to the world outside the classroom acts as a powerful stimulus to
academic work.
What kind of applied science should be done in <strong>school</strong>s? A hint has already
been given above when discussing ‘science for action’: we must now look at this
in more detail.
10.5 Incorporation of technology into <strong>school</strong> <strong>physics</strong> programmes
No country has appreciated more than the USSR the need to incorporate
references to technology in the basic <strong>physics</strong> courses in their secondary <strong>school</strong>s.
They believe that <strong>physics</strong> has entered so deeply and so widely into their life that
139 Incorporation of Technology into Schools Physics Programmes

unless one understands the foundations of <strong>physics</strong> and its links with applied
knowledge one cannot call oneself an educated person. Science knows no example
of such rapid and triumphant development as that of <strong>physics</strong>, which has
contributed so much to other fields of knowledge. Physics is certainly the basic
science; it provides the theory behind technology; it is the foundation of technical
progress and the basis of many fields of theoretical and applied knowledge.
The applications of <strong>physics</strong> should be appreciated not only in a relatively
narrow engineering-technological sense, but in a sufficiently wide range to embrace
all the fundamental fields of human knowledge. Thus, for example, it is
considered essential in the USSR to give pupils evidence of the exploitation of
the successes of <strong>physics</strong> in medicine (health <strong>physics</strong>), in biology (bio<strong>physics</strong>), in
agriculture, in geology (geo<strong>physics</strong>) and in other sciences from chemistry to
astronomy and cosmology.
In the US S R, as in other countries, there are general and specialized secondary
<strong>school</strong>s. The importance attached to <strong>physics</strong> is characteristic of both and is of
fundamental national significance, since for the majority of young people their
education in <strong>physics</strong> ends at the end of the secondary <strong>school</strong>. In those countries
like the US S R where between eight and eleven years of education are compulsory
the secondary <strong>school</strong> is responsible for the general cultural level of the
people as a whole, including the vital part of that culture which concerns <strong>physics</strong>
and the role it plays in life.
In the specialized secondary <strong>school</strong>s all <strong>physics</strong> phenomena and their theory
which concern the <strong>school</strong>’s speciality are taught on a wider and deeper basis than
is envisaged by the syllabus of the general secondary <strong>school</strong>. The corresponding
applied side is also taught in greater detail and depth, even though it may have
less significance, when the pupils are going on to higher technical education,
because the corresponding material wil be reflected in the syllabuses of the
<strong>physics</strong> courses in the higher establishment on an even wider and deeper basis.
Much attention is given in the <strong>physics</strong> syllabuses of all Soviet secondary <strong>school</strong>s
to the close links and interdependence which exist between technology and
<strong>physics</strong>, both classical and contemporary; to the fact that the development of
technology is based on physical discoveries and the speed with which they are
introduced into technology; also to the possibilities in experimental <strong>physics</strong>
which depend on the modernization of laboratory equipment which, in turn,
heavily depends on technological development. It is emphasized that it is precisely
this mutual influence of <strong>physics</strong> and technology which leads to violently
accelerating speeds of development in both fields.
This demonstration of the links between <strong>physics</strong> and technology is not confined
to the introductory stages of the <strong>physics</strong> courses, but pervades the whole
course in its systematic, progressive stages.
10.5.1 Some technical applications of<strong>physics</strong> in Souiet<strong>physics</strong> courses
Listed below are some of the technical applications of <strong>physics</strong> which form an
integral part of the <strong>physics</strong> syllabus in Soviet secondary <strong>school</strong>s :
140 Physics and Technology

Statics. Pulley systems, cranes, the inclined plane and applications of the principle
of the wedge, screws.
Kiiienzatics. Elements of ballistics.
Mechanics. Watt’s centrifugal regulator, the centrifugal pump, details of cosmic
flights.
Oscillations arid waves. Clock mechanisms, damping of oscillations in electrical
measuring and other devices; frequency meters; the recording and reproduction
of sound.
Hydrodynamics and aerodynaniics. Pumps, hydraulic presses, carburettors, the
ejector. the pulverizer, wind tunnels and aerodynamic forces, streamlining, turbines,
hydro-electric power stations.
Moleczilar,forces. The coupling of Johannsen’s bars.
Thermal expansion. Gas, liquid and bimetallic thermometers.
Conzpressed gases. The compressor, pneumatic pick, pneumatic brakes.
Surface tension. Selective flotation, hydrophobing fabrics, capillary lubrication.
The solid body. Forging, stamping, wire-drawing, rolling.
The changing of states. Casting, the production and use of liquid gases.
Gas laws and the foundutions of therrnod.ynainics. The steam engine, the fire-tube
boiler, the steam-tube boiler, the single-pass boiler, the steam turbine, internal
combustion engines (petrol and diesel), contemporary jet engines.
Electrostatics. Basic technical applications of insulator, conductors and condensers,
accelerating machines.
Current electricit-v. Resistance thermometry, safety fuses, high-voltage transmission
lines, thermoelectrical effects.
Electrolytes. Electrolytic refining, production of aluminium, galvanizing, storage
batteries.
Therrnoelectronics. Thermoelectric devices, spark voltmeter, electro-erosion and
its applications (insertion of apertures and hard-fusing coverings). applications
of arcs, projectors, electrometallurgy, electric welding.
Electroinagnetism. Electromagnets, electromagnetic relay and its applications.
microphones, loudspeakers, the telephone, electromagnetic damping.
Alternating current. Simple generators, hydroturbine electric generators, electric
motors, transformers, valve rectifiers, semiconductor rectifiers. direct-current
generators, power stations.
Electronics and electromugnetic waves. Valves, transistors, radio receivers, photoelectric
cell and its applications, the oscilloscope, radiolocation, sound recording
and reproduction, television.
Optics. The camera, projectors, microscopes. telescopes, binoculars, the spectrometer,
spectral analysis.
X-rays. Uses of X-rays in fault detection and structural analysis.
141
Incorporation of Technology in Schools Physics Programmes

Nuclear <strong>physics</strong>. Technical applications of radioisotopes, including radioactive
tracers and use to replace X-ray <strong>source</strong>s, nuclear fission, applied functions of
nuclear reactors, nuclear power stations, thermonuclear synthesis and possible
applications.
Such topics included in the syllabus need regular scrutiny to include the achievements
of recent years. This is important from two points of view: firstly, in order
to improve the general preparation of young people for direct practical activity
or for the continuance of their technical education at a higher level and, secondly,
in order to heighten their interest in <strong>physics</strong> as the foremost motive force of
technology. One is sometimes amazed at the extent to which modern children
have time to absorb ideas about the latest achievements of technical <strong>physics</strong> even
before taking <strong>physics</strong> in <strong>school</strong>. As a result it is difficult to interest the modern
<strong>school</strong>child with something in this field other than by bringing him the very latest
technical developments.
This tradition of incorporating technical applications into the basic <strong>physics</strong> is
of long standing in the US S R and is helped by the central organization of education
in each state of the USSR. Extensive use is made of short films and, for
example, every <strong>school</strong> teaching about hydrostatic pressure would have ready
access to a film on hydraulic presses so that the application of the principles to
the outside world could be appreciated. But the system imposes considerable
demands to keep visual material up-to-date. Furthermore, the tempo of the
development of modern technology is so rapid that not only the secondary<strong>school</strong>
teacher but also the lecturers in higher education have the greatest difficulty
in keeping up with the latest innovations of applied <strong>physics</strong>.
Another interesting feature of <strong>physics</strong> education in the USSR is the extent to
which industrial visits form an integral part of <strong>physics</strong> courses. These are carefully
organized to show the relevance of the topics being discussed in the classroom
to the applications outside.
10.6 Involvement of pupils
Highly impressive as is the technique in the USSR for incorporating technology
in the basic <strong>physics</strong> course, and similar developments are reported from Japan,
there are some who would view it as telling pupils about technology and not involving
them in it. The discussion earlier in this chapter on sciencefor action
suggests that there may be advantages in allowing pupils to be involved themselves.
Work on this is currently going on in various parts of the world. It will be
interesting to see the outcome of the Engineering Concepts Curriculum Project
in the US A. In the meantime work is being done in the United Kingdom and it
would seem appropriate to conclude this chapter with some reference to the
Schools Council Project Technology and also to the contribution being made in
the Nuffield A-level <strong>physics</strong> programme, as examples of work which might meet
the requirements specified earlier.
142 Physics and Technology

10.7 Project technology
Work on this Schools Council project began in the UK in 1966. It defines technology
as the purposeful application of man’s knowledge of materials, <strong>source</strong>s of
energy and natural phenomena, and it accepts that the relationship between
technology and society must be reflected in the <strong>school</strong> curriculum. It seeks
specifically to encourage technical activities in <strong>school</strong>s and thereby to develop a
range of abilities and provide motives which are often overlooked by more
traditional approaches.
It should be noted that the emphasis is on technological activities. The pupils
must not feel passive recipients, for in that way they can be overawed or restricted
in their ability to derive benefit from the process. Instead they are led through
creative activity to a realization of the importance and relevance of technology.
and to see how science can be used to practical effect.
The <strong>school</strong>s involved with the project (and it is significant that there are already
over a thousand) are encouraged to identify and foster whatever abilities pupils
may have, rather than to guide them into activities which develop only a restricted
range of abilities. An important feature of the work is that the pupils need to be
involved in making decisions. They are involved in the process of recognizing a
need and identifying a problem, designing a solution to the problem within the
limits of re<strong>source</strong>s available and finally bringing the solution to reality and
thereby meeting the need.
The activities would be ruined if any of them became routine, so there must be
an open-endedness about them. For this reason the material provided by the
project aims to give inspirational guidance, to suggest a field of activity and
identify some of the obstacles to be overcome or to be avoided, but it deliberately
does not give too much specific information. Little is achieved by routine work
following cookery-book instructions; initiative must rather be leftto the pupils so
that they come toappreciate their own capabilities, based on their experience and
the scientific knowledge they have already acquired.
The range of activities is unlimited: work on structures, logic circuits and
computers, fluid flow, home technology, engines, plastics, fibres, electronics and
control technology. Sometimes an activity involves a group of twelve or more
children, for example the <strong>school</strong> which designs and builds its own hovercraft.
Sometimes several <strong>school</strong>s have collaborated; for example three <strong>school</strong>s used
scrap and surplus material to build a machine to clear weed and debris from a
disused canal, and so successfully was this done that the canal was once again
made navigable and restored as an amenity. One <strong>school</strong> designed and built the
pontoons, another the paddle propulsion gear, the third the final assembly. Other
project activities may involve small groups of pupils or in some cases they may
work individually.
The following is a list of typical activities :
Logic control systems for model railways
Experimental metallurgy and materials testing
Building a radio-telescope
143 Project Technology

Figure 3 (a) Moonraker I at Dauntsey's School
(photo. Bath and Wilts Evening Chronicle)
Investigating the grip of car tyres on ice
The linear induction motor
Car-door safety devices
Building a wind-powered generator
Strain gauges as a means of producing a sensitive transducer
Making an automated metal-deposition machine
Schlieren techniques to investigate change of refractive index of a gas
Air-pollution testing machine
Problems in friction and lubrication
Automatic and programmed control of a greenhouse
Reaction timers
Automatic scene-changing apparatus
Investigation of aerofoil sections
Light modulation by piezo-electric effect
Thrust of a solid-fuel rocket motor
Action of gyroscopes
Absorption of radioactivity by aluminium
Use of a crystal to detect pressure variations in an engine
I44
Physics and Technology

A girl in one <strong>school</strong> designed and built her own analog computer. Two boys
in another set out to build a vehicle capable of steering itself towards a light
<strong>source</strong>: the truck was four-wheeled, each rear wheel being geared to its own
motor; the motors were controlled by photocells in suitable screening tubes, connected
in simple transistor circuits which they designed themselves.
Serziing society. Young people today are just as idealistic as the young have
always been. M. W. Thring writes:
It is the idealisticdesire of the young to see a better society and serve humanity in some way
which is the main reason fortheir disagreement with so much that they see going on around
them. I think the most terrifying feature of the whole of our educational system really is
that it does not give them anything for this idealism to feed on. They want to take up a
career which will serve society and this, of course, is one of the reasons why they very often
choose social science at university. because they think this means they can serve society.
Professor Thring (1969) puts the case that one of the best ways of serving society,
humanity and the individual human being is through technology and that it is
such activities as project technology that introduce pupils to this. It is significant
what a response there is to work on projects to help the handicapped or disabled.
for example to build a page-turner for a disabled person in a hospital bed. The
following is an account of a project undertaken by girls at one secondary <strong>school</strong> :
The <strong>school</strong> science department developed a device to give warning in cases where elderly
people living alone collapse through accident or illness and are unable to summon help.
Systems previously in use depended on the elderly person operating a push-button. lever
or cord to switch on a warning bell or light at the front of the house, but such systems had
the drawback that they required manual operation. and were therefore useless in situations
of greatest need, such as sudden and unexpected collapse. It seemed surprising that no one
had thought to devise an automatic system using photocells and electronic circuitry. We
assumed that a person who was up and about would need to prepare food. Having regard
to the hours of sleep, if a period of ten hours passed without the kitchen door being opened,
it would indicate that all was not well, and a warning would be given.
The girls were asked to devise a mechanism that would cause a bell to ring if a door
remained closed for a continuous period of ten hours. During the next few weeks diagrams
were handed in of devices using springs, weights, pulleys. elastic and even dripping water.
We realized that our basic requirement was a timing mechanism: an electric time-switch
was needed. It now seemed a simple matter to arrange for the time-switch to be pulled back
to the ten hour mark by the movement of a door. We tried without success.
The girls then suggested other mechanical actions which are regularly performed in a
house. and which could be used to reset the time-switch. Many were investigated. Eventually,
after minor adaptations. we found that the movement of the arm of the lavatory tank
met all our requirements. The time-switch was mounted on the wall at the side of the
lavatory tank and a piece of stringconnected the setting lever of the switch to the arm of the
tank. Each time the chain is pulled, the setting lever is returned to the ten hour mark. If a
continuous period of ten hours passes without the lavatory being flushed. the time-switch
brings into operation a warning light in the front of the house or the home of a neighbour.
145 Project Technology

Figure 3 (b) Device for turning pages (St. Thomas More School)

Figure 3 (d) Automated metal deposition machine (Danum Grammar School)
The outconic was published in two national papers and enquiries \\ere rcccived
from wclfiire departments of \xrioti\ local authoritieb: it in\ol\cd so~i~e good
applicd work and the satisfaction to the girls in bringing tlic project to a satisl';tctorv
conclusion. despite a11 the frustrations ~ind dihiippointments on the 1~2y.
must haw shown them thc value of technology and hclpcd to cmphasi7e thc relewncc
ofthe science done in the classroom.
A scicnce te:icher often feels himself in dilficulty \i hen introducing tcchnolog!.
Hc feels a lack of knowledgc of the applications of science LIS ;I redt of his training
in 'pure' science and ;i lack of expcricncc 01' induztry and technc)lc,piccll
activity. Hc may lack conlidence in his ability to promote open-ended tcchnologiciil
acti\'itics. It is becauw of this that Project Technolo:! prepares tcaching
material on technological themes: it produces guidance boc>klctj on the design
:ind construction of eyuipmcnt \\ hich makes possible further technological acti-
\,ities. One such booklct. for example, is concerned \\ ith practical applications of
Bernoulli's thcorem. in which :in inexpensive rig is advoc~itcd tising ;I stan-
147 Project Technology

dard car carburettor, another with details on how to set up a low-cost engine
test bed, another on materials testing equipment and so on. The project has set
up an information service on modern industrial applications of scientific principles
currently taught in <strong>school</strong>s. It is of course carrying out an evaluation of the
work as an educational method and it is much concerned with training teachers
and establishing local centres for liaison with industry and as a forum for ideas to
be exchanged and discussed.
148 Physics and Technology

10.8 Nuffield advanced-level <strong>physics</strong>
Whereas the Nuffield 0-level project was concerned with providing <strong>physics</strong> for
the future citizen, the A-level course is taken when some specialization has
begun. The pupils wil include those going to a university to study 'pure' science,
but there will also be many future engineers, applied scientists, doctors, biologists
and agriculturalists. This is not the place to give details of this project (see
Appendix B.8) but there are certain parts of the course relevant to the future
engineer and technologist.
The practical uses of <strong>physics</strong> and the ways in which engineers approach problems
receive some emphasis: certain sections of the course. such as those on
materials and on magnetic fields and induction, have their teaching developed
in an 'applied' rather than in a 'pure' spirit. Furthermore. background material
attempts to do justice to the applications of <strong>physics</strong>, to presenting <strong>physics</strong> in
relation to meeting human needs and to emphasizing the social significance of
scientific ideas and methods. For example, there wil be pupil material on composite
materials, electrochemical machining, electric traction, bridge design, uses
of radioisotopes, feedback control systems and so on.
The experimental work is designed to enable pupils to investigate relationships
and to raise problems which are then the basis for discussion. An interesting
feature is the technique much used in the course to get pupils to tackle a variety of
experiments and then to report back to the class as a whole on the results of their
particular experiments. Having to report to their colleagues plays a basic role in
developing communication skills. and attempts to meet some of the criticisms
mentioned earlier in this chapter about the inability of students to report clearly.
Pupils can learn much from each other.
10.8.1 The electronics section
This section of the course is almost wholly applied. giving an opportunity for
pupils to work in the engineer's spirit of using devices to do a job, and also showing
a wealth of practical applications. <strong>Teaching</strong> electronics is not new, but teaching
with traditional apparatus was often concerned primarily with the characteristics
of components, the analytical approach of the 'pure' scientist investigating
M ~ Jsomething I works as it does. <strong>Teaching</strong> using the electronic modules, as
developed for the Nuffield project, is not particularly concerned with why a
module works as it does, but with what it Mill do. The concern is with synthesis,
putting units together to serve a purpose, the usual concern of the engineer. It is
a systems approach, involving pupils in the processes and methods of one
branch of technology. The writer has seen the enthusiasm of boys, not necessarily
electronically inclined, using the material to produce automatic lighting systems,
binary adders, a counter, a reaction timer, an oscillator, a frequency meter, a
system to control traffic lights or to control a marshalling yard automatically
and even an electronic organ to play a tune continuously. Some biologists
149 Nuffield Advanced-Level Physics

epeating Pavlov’s experiments on mice have used the equipment as an automatic
method of measuring their IQ !
10.8.2 The investigations
About 10 per cent of the time of the course has been set aside for two investigations,
one in each year of the two-year course. In these each pupil works on a
small novel problem of his or her own choice, not necessarily (or even usually)
closely related to other experimental work in the course; for this the choice of
apparatus and the devising of a method is left to the pupil. It requires the pupil to
identify a problem and set about solving it. The teacher becomes merely a
consultant to be approached in difficulty and always available to encourage
where necessary. Experience has shown that these investigations arouse great
interest and enthusiasm; they certainly develop individual involvement and
sometimes creative skillsas well.The range of investigations is wide, as is the case
with Project Technology already discussed: many wil be similar to those undertaken
in Project Technology though usually of shorter duration. It is hoped that
such work will help students to begin to learn how to inquire and how to solve
problems for themselves.
150 Physics and Technology

I1 Physics and Mathematics
This edited chapter incorporates contributions from Bryan Thwaites of the Schools
Mathematics Project, R. Lewis of Chelsea College, J. G. Wilson of Leeds University and
two industrial scientists, J. Thomson and M. Milbourn. The main contribution comes
from A. W. Fuller, formerly HMI of the UK, now Director of the Continuing
Mathematics Project at the University of Sussex.
1 1.1 Introduction
Perhaps this chapter has presented more difficulties in its preparation than any
other. Conferences, both national and international, continue to urge that the
closest links should be established between the teaching of mathematics and the
teaching of <strong>physics</strong>. We hear pleas that curricula should be adjusted so as to
accommodate coordination between the two disciplines. And yet depressingly
little work has been done on it. This volume testifies to the very substantial
amount of thought that is being given to, and the work that is being done on. the
teaching of <strong>physics</strong>. The number of modem mathematics programmes exceeds
the number of those on <strong>physics</strong>, perhaps because it is a much less costly process to
develop a new mathematics course. Yet there is an almost total dearth of integrated
<strong>physics</strong> and mathematics programmes, despite the obvious advantages of
such integration to both disciplines.
Internationally, the problem is accentuated by the wide differences in the level
of mathematics teaching throughout the world. Some countries, particularly
those in Western Europe, have such a strong tradition of mathematics teaching
that ideas of double line integrals, second-order differential equations and the
use of complex numbers and complex trigonometry are already familiar in the
higher grades of a secondary <strong>school</strong>. There are other countries which do no calculus
at that level and yet others, including highly developed countries, where
secondary <strong>school</strong>s cannot rely in their science teaching on more than the rudiments
of algebra, and may even find a complete ignorance of trigonometry.
The problem is not made any easier by the introduction of much 'modern
mathematics'. Pupils may now have a knowledge of set theory or matrices, or
they may be familiar with Boolean arithmetic, but science teachers complain that
they have lost the ability to multiply by 0.05 or to divide by f. A cynic might
remark that in traditional mathematics the pupil could calculate with numbers
151 Introduction

without knowing what they were, whereas now he can say a lot about what
numbers are without being able to calculate with them.
Perhaps the mathematicians, in revising the content of their syllabuses, have
not always considered the needs of the scientist. Against this Bryan Thwaites
writes :
I think that over the years I have come to the conclusion that at <strong>school</strong> level, just as much as
university level, one should try and get away from the concept of mathematics as a service
subject. Quite apart from one’s basic attitudes towards mathematics as a subject in its own
right, there is the purely practical problem that nowadays the applications of mathematics
are so widespread, and increasing at such a rate, that once one started talking about
mathematics for <strong>physics</strong> one would have to go on to talk about mathematics for geologists,
classicists, modem linguists and all the rest. In other words, my own view is that mathematical
concepts are fastbecoming central to all intellectual disciplines and that therefore
the right approach is to consider a single body of mathematical teaching. which is satisfactory
in itselfand also lays the foundations for applications and mathematical modelling
in a great variety of situations.
Although the scientist complains that modern mathematics programmes do
not consider fully enough the needs of the scientist, perhaps equally the scientist
has been too much concerned with the use he wishes to make of mathematics as a
tool and has failed to notice what the mathematician is trying to do in those new
programmes. This is discussed in the section of this chapter on the structures of
elementary mathematics courses where it is stressed that mathematics does have
a structure peculiar to itself and that there is therefore some danger in any
attempt to build a mathematics course merely around the demands of science.
On the other side there is the story told by C. N. Yang, expressing the disenchantment
of some physicists with the mathematician.
There is a story circulating among us describing the feelings of a physicist when he consults
a mathematician. A man carried a large bundle of dirty clothes and searched for a laundry
without success fora long time. He was greatly relieved when he finally found a shop displaying
a sign ‘Laundry done here’ in the window. He went in and dumped the bundle on
the counter. The man behind the counter said:
‘What’s this?’
‘I want to have these laundered.’
‘We do not do laundry here.’
‘But you have a sign in the window advertising that you do laundry.’
‘Oh! That! We only make signs.’
There is indeed this danger that some mathematics courses are only concerned
with making signs. Yet we do want to involve mathematics in the realities of our
concern as physicists.
But the authors of new mathematics programmes write (Fletcher, 1964):
The teaching of mathematics also needs to be better integrated with contemporay applications
in industry and research; indeed these applications should often be the vehicle by
which the subject is taught; to regard them merely as ancillary illustration. as a sauce to be
added after the meal is cooked, is to misunderstand their role in teaching.
152 Physics and Mathematics

And again :
Mathematics does not start with the finished theorem in the text<strong>books</strong>; it starts from situations.
Before the first resultsare achieved there is a period of discovery. creation, error. discarding
and accepting. The situations from which mathematics starts are rich and varied.
The start may be a puzzle, an unsolved problem from the previous lesson, a piece of
apparatus, a portion of the textbook or a problem from the world outside. Mathematics
involves the proLzss of abstraction: starting with the concrete situation. recognizing corresponding
structures and using one structure to solve problems presented by another. Our
concern is with the whole process and not merely with the techniques of the internal
operations within one system.
Professor Thwaites writes that the teaching of modern mathematics ‘needs
multitudes of applications at all levels of these basic concepts, and these examples
should be as realistic and as meaningful as possible for the pupils. In our view, a
deep involvement with applications is a criterion of the quality of a <strong>school</strong> mathematics
course.’ Physics is notoriously good at providing situations : perhaps there
is scope for collaboration.
11.2 What the customer wants
Before looking further at modern mathematics it might be wise to look at the
views first of the universities, then of industry. J. G. Wilson, the head of the
Physics Department of Leeds University. writes as follows on the place of mathematics
:
There is a certain mathematical content in all effective <strong>physics</strong>. Mathematical formulations
will often arise for the student, at <strong>school</strong> and at a university, and they assist in sharpening the
precision of his ideas which is wholly good. But what we have actively to discourage is the
miserable memorizing of ‘proofs’ and formulae which is no part of the student’s persisting
understanding of <strong>physics</strong>, but regrettably is deplorably convenient as an examination
technique.
We all know that. while some activities of <strong>physics</strong> indeed demand high mathematical
competence, many physicists do work of distinction with only modest callson mathematical
methods (anybody who doubts this may profitably read through the published work of
recent Nobel Prizemen). We must not hazard the supply of physicists by demanding indiscriminately
a high level of mathematical attainment both for those to whom it is a natural
approach and from those who wil certainly be driven to sacrifice something.much more
important to find the time and energy to master it.
Another probably controversial view comes from an industrial scientist, J.
Thomson:
Mathematics should be presented first as a tool, allowing a quantitative result to be obtained
quickly and accurately, and only in the later stages of training should its other
function be disclosed, namely that its symbolism offers a shorthand generalization of value
in suggesting a fresh attack on a problem. Most important of all it should be made very
clear to the student that mathematical work is not scientificallycreative.
This is of great importance in view of the distorted outlook possessed by many of our
younger graduates. Almost all directors of scientificestablishments confirm that the <strong>physics</strong>
153 What the Customer Wants

graduate of today regards mathematics as we must imagine the ancient alchemists regarded
the philosopher’s stone. Mathematicians themselves, of whom I am one, are quick to admit
that creative thought can only at best be suggested by transformations, but the obeisance of
the physicist, chemist and engineer to this tool of their trades is something which requires
correction. I can confirm from personal experience that it is not uncommon for a physicist
who has been asked to uncover new information to imagine that he can do so by futile
gymnastics in symbolism.
The secondary reason for pressing this point of view is that even the brilliant student is
occasionally caught napping by mathematics and is led to imagine that he understands a
relationship because he can write down an equation to describe one aspect of it. Reminding
ourselves that we are searching for methods of increasing our potential of talent, we must
be very careful not to mislead the inexperienced by a too facile use of symbols. As one
brought up in a severely mathematical atmosphere, I speak with feeling.
This brings me to the other side of the same coin. If a teacher uses mathematics to do
more than give arithmetical value to his description of relationships, he is failing in his duty
to his pupils. It is so easy to describe phenomena symbolically, and so satisfying to generalize
on the basis of symbols, that it is not surprising that we all fall into the trap from time to
time. A good exercise is to explain Fraunhofer diffraction without the use of mathematics,
or, at least, only using the most elementary arithmetic. A better exercise is to explain the
variation of Newtonian mass with velocity without introducing a four-dimensional system.
I firmly believe that if a teacher has to have recourse to mathematics for any other purpose
than a computational one, he does not properly understand what he is trying to describe.
Finally another industrial physicist, M. Milbourn, writes :
Training in mathematics is valuable. but it does not replace the need for experimental
ability. Mathematics, in fact, is no more than a tool to provide a formalized approach to
logical thinking. An appreciation of statisticsand of statisticalmethods is desirable because
it indicates the nature of variabilityand of errors. In industrial work, experimental results
seldom have the accuracy of those on which the teaching of <strong>physics</strong> is based, because the
materials and processes encountered are never perfect or homogeneous. This can be one of
the hardest lessons for a young graduate to learn, but I would not recommend that the
standard of perfection taught in universities should be lowered in consequence, although it
should be combined with an appreciation of inaccuracies likely to arise in applied work.
There are some fundamentally important points in these three contributions. *
Let us now look more closely at collaboration in teaching.
11.3 The need for collaboration in <strong>physics</strong> and mathematics teaching
It must be admitted that during the past forty years the attitude to mathematics
prevalent amongst science teachers has too often been a preoccupation with
excision. On the assumption that mathematics is difficult or badly taught and
* The view expressed by J. Thomson on the creative aspect of mathematics is not that of A. W. Fuller,
who writes: ‘I accept and endorse J. Thomson’s indictment of the students’ fondness for mere symholshoving
as a substitute for sound argument, hut I cannot agree with his view of the place of Mathematics
in the learning of science, nor with his opinion that Mathematical work is not scientifically
creative. Admittedly this is true of much of a student’s Mathematics as it is of much of his science.’
The two different views are deliberately included here, the reader must make his own decision - Ed.
154 Physics and Mathematics

that few pupils can profit from mathematical arguments, anything mathematical
that could be cut from <strong>physics</strong> lessons should be eliminated. This attitude was
recently expressed by an able young <strong>physics</strong> teacher in the two-pronged sentence :
‘You must not make one subject depend on another, and some of our pupils are
very weak.’ This is all very well, but it is rather like saying that because everyone
cannot have children, no one should! There are in fact some very good arguments
for collaboration.
(a) However weak pupils may be, they are likely to have a curriculum which
includes a substantial amount of mathematics for some five or more years of
secondary education. If this teaching can be conceived as associated with and
beneficial to the learning of <strong>physics</strong> (and other subjects), then cooperation is
called for between the teaching, and preferably between the teachers, of the two
subjects for the benefit of the pupils.
(b) Physics furnishes many of the readiest and most significant applications of
secondary-<strong>school</strong> mathematics. The recent increase in the mechanical content of
secondary-<strong>school</strong> <strong>physics</strong> (PS SC and Nuffield 0-level, for instance) involves the
pupil in some of the richest <strong>source</strong>s of mathematical relations vital at the secondary
stage. At the lowest level of interchange the mathematics teacher cannot leave
the most fruitful mathematical concepts (area under a curve and rates of change,
for example) to be developed solely by the science teacher.
(c) It is accepted that part of the present revolution in mathematics teaching lies
in the affirmation of the general principle that mathematical concepts should be
introduced intuitively through, and by means of, familiar applications. This technique
is sometimes described as ‘ mathematizing a situation.’ The real or simulated
situation comes first, the analysis next, and generalization, abstraction and
possibly eventual axiomatization come later.
The depth and form of the abstract development wil range widely according
to the maturity. ability and taste of the pupils. But the order of presentation, with
the concrete situation first, is by and large the same for all pupils.
This general principle does not directly affect the teachers of other subjects so
long as the concrete situation is one with which the pupils are already familiar, or
which can readily be presented and made viable in the mathematics classroom so
that it can be experimented with mentally. But as the pupils progress it is necessary
for the mathematics teacher to draw increasingly on more sophisticated experience,
such as can be provided by the <strong>physics</strong> department. The provision of
mechanics experiments, observations on alternating currents, wave phenomena
using ripple tanks, transmission lines and wave guides is more appropriate to
<strong>physics</strong>.
Ticker-tape, indicating spatial progress at regular time intervals, may well be
used in the <strong>physics</strong> laboratory, but it need not remain there exclusively. It should
be available to the teacher of mathematics, who should be prepared to use it as
the basis of mathematics lessons. If, in their turn, these lessons can point towards
further relations which can profitably be tested in the laboratory in science lessons,
so much the better.
155 The Need for Collaboration in Physics and Mathematics <strong>Teaching</strong>

This interchange wil help to reassure the pupils of collaboration between
departments and establish the unity of topics that are conveniently, but often
artificially, fragmented for pedagogical convenience.
(d) For those pupils who are going to be professional users of <strong>physics</strong>, engineers
for instance, the mathematical formulation of physical results is essential. Theirs
will be increasingly the world of automation and computers, and computers are
notoriously precise.
(e) This item will apply only to a small minority of pupils, but it is not necessarily
unimportant: the necessity for mathematical argument at the highest levels of
invention in the physical sciences is obvious. The part played by mathematics in
the historical development of theories of planetary motion and gravitational
theory, in electromagnetism, atomic structure, electromagnetic wave propagation,
relativity, and quantum and wave mechanics, in short the whole basis of
modern <strong>physics</strong>, makes it imperative for the future creative physicist to understand
as fully as possible all the mathematical structures involved in his work.
Group theory, for instance, is needed today by the research worker both in solidstate
<strong>physics</strong> and in crystallography, and the computer is his slide rule.
11.4
The structures of elementary mathematics
The structures around which modem mathematics courses are usually built are
vector spaces, analysis and probability and statistics. To these should be added
computation, since it is involved in all three and draws on them all.The same is
true of such universal concepts as sets and relations (including mappings and
operations). These, together with the mathematical use of symbols, could be
included under a general heading mathematical use and methods.
Vector spaces covers more or less the whole of traditional algebra and geometry,
the latter in its Cartesian rather than its Euclidean form. But its applications
are wider and they include the vectorial relations of mechanics and lead to
such concepts as eigenvalues and eigenvectors, and through analysis to eigenfunctions,
which are essential concepts for an appreciation of the mathematical
models of atomic structure.
Analysis at secondary-<strong>school</strong> level concerns little more than differential and
integral calculus with an introduction to differential and integral equations.
Probability and statistics are being more widely and more systematically taught.
They draw on the other two structures, and in the early stages they provide good
opportunities for meaningful computation and graphical illustration. They make
perhaps the most significant use of set notation and the operations of intersection
and union, and provide a valuable example of ‘measure’, probability being a
measure of a special kind imposed on subsets of the sample space. They also
introduce a new concept of almost universal application: a posteriori reasoning.
Almost all our experience involves sampling, the samples being drawn from
populations about which we have only partial information. We infer properties
of the population from our experience of the samples.
156 Physics and Mathematics

Properly taught. there are few aspects of a mathematical education based on
the above outline that do not impinge on the learning of <strong>physics</strong>.
Such a sweeping view of elementary mathematics wil not appeal to everyone,
and will. by itself, convince no one. But it is outlined here to emphasize that
mathematics does have a structure peculiar to itself with its own pedagogical
traditions. It would be a mistake to try to build a mathematics course around the
demands of science or any other subject.
11.5 The detailed points of association
Some of the points of association have already been indicated in this chapter: the
dependence of modern mathematics teaching on situations and the wealth of
these to be found in <strong>physics</strong>, vectorial work in mechanics, work on rates of
growth and areas under curves, the increasing importance to the scientist of
probability and statistics. the desirability of close association in work on wave
phenomena, a.c. work and mechanics. And when one of the objectives of a
modern mathematics programme is said to be that ‘the idea of graphs, that is, of
the possible states of a system, and of the operative connections between the
states, is one which should now permeate all the teaching of mathematics’, how
can this fail to be welcomed with open arms by the physicist? It is impossible in a
chapter like this to give more than one or two examples of association between
mathematics and <strong>physics</strong> teaching, but it seemed sensible to do so if only as an
indication that much work still needs to be done.
11.5.1 Algebra
The mastering of algebraic symbolism is much more subtle than traditional
teaching would suggest, and where this is realized modern teaching should be
more effective. Mastery of symbolism is possibly the main stumbling block of the
average student of mathematics. Equations such as
L = L,(1 + ar)
ought to be dealt with in mathematics lessons where they can be related to simple
interest and other linear relations. It may even be preferable for the symbolic
expression to be derived by the mathematics teacher from the results of laboratory
experiments. Where mappings figure in the syllabus, science can provide
many examples, not all of which are suited to analytical approximation when
they are encountered. But a mapping is a mapping! The fact is more important
than the form.
11.5.2 Matrices
These are the operators of a vector space and provide perhaps the most important
innovation in elementary mathematics for the <strong>physics</strong> teacher to consider. Their
classical application is to linear electrical circuits. In particular, four-terminal
157 The Detailed Points of Association

networks provide a precise model for 2 x 2 matrix algebra in the form
where M is a 2 x 2 matrix whose elements are rational functions of the circuit
constants (R, C and L); if resistive elements only occur, the elements wil be positive
real numbers; if capacitative or inductive elements are present, complex
numbers are involved.
The eigenvectors (characteristic vectors) of this matrix define the characteristic
impedance of the network. The extension of this pattern to iterative networks
(filters) and transmission lines is mathematically not difficult for sixth-form
specialists. This leads to the next important problem.
11 S.3 Electrical circuits and electromagnetic phenomena
Most mathematics teachers are unfamiliar with alternating-current circuits, but
a knowledge of these is surely as important to the modern student of <strong>physics</strong> as a
knowledge of classical mechanics. Whereas the mathematics teacher may be expected
to be familiar with Newton’s second law he may never have heard of
Faraday’s law, its electromagnetic analogue. When dealing with energy considerations
and simple harmonic oscillations he wil freely manipulate
dV X dx
F = m- and F= A-, where V=dt
a dt
(x is the extension of a spring of natural length a), but know nothing of
v = L- dI and V = -, Q where I = -.dQ
dt c dt
The use of modern teaching equipment, in the form of slow oscillators, largevalued
inductors and capacitors, and higher-frequency circuits, makes it possible
for the mathematics teacher to assimilate reasonably quickly the knowledge that
his pupils are acquiring in the <strong>physics</strong> laboratory; and if he does this, he is much
better placed to use his mathematics, especially calculus and the energy-relation
formulae, in a wider context. In this way, he may even be led to an interest in wave
phenomena.
11.5.4 Wavephenomena
The recent introduction of ripple tanks, stroboscopic devices and other waveproducing
and wave-observing equipment has not so far been matched by a corresponding
treatment of waves as mathematical patterns. However, many
teachers of mathematics do treat trigonometry in a manner that is more helpful
than it used to be when no angle more than 360” was referred to. Even early treatments
of trigonometry encourage consideration of the infinite graphs for sin x
and cos x: this is made possible by the more extensive teaching of Cartesian
158 Physics and Mathematics

geometry and a sounder treatment of directed numbers in the early secondary
years.
Much more could be done in the mathematics classroom to help the pupil in
his understanding of wave phenomena. A recent experiment in the United States
suggests one possible line of development with quite young children. Beginning
with simple periodic sequences (days of the week, meals of the day etc.) the idea
of repeating sequences is first established. Then linear numerical distributions
that vary with time are presented. Suppose one considers two sequences of numbers,
one moving to the left and the other to the right.
- a b c d e f g h -
- p q r s t 11 v w t -
Each moves one step between the time 0, 1,2. . .
The resultant time sequence at time 0 is
a+p b+q c+r
d+s e+t f+u y+o h+w
At time + 1. the resultant sequence, in corresponding positions is
... a+r b+s c+t d+u e+o f+w ....
And at time + 2,
a+t b+u C+L‘ tl+w ....
What is the relation between the resultant number at a particular position in any
one row and the neighbouring numbers in previous rows?
For example b + u = (b +s) + (d+ U) -(d+s).
In general
n(x, t+ 2) = n(x- 1, t+ l)+n(x+ 1, t+ 1) -n(s, 1).
Given this relation. which can be formulated without this symbolism for the
benefit of young pupils. it is possible to ‘create’ waves of numbers moving to
right or left, interfering to make beats or standing waves so as to give muchneeded
practice in manipulating small directed numbers. Much later the same
relation can be made to yield the standard second-order partial differential equation
for a one-dimensional wave.
At a higher level it is possible to deal with the speed of propagation of waves in
a manner less mathematically sophisticated than usual. One considers a uniform
transmission line fed from a direct-current <strong>source</strong> and makes the following
assumptions that may be justified or not, as the science teacher likes:
(a) The total line capacitance is C farads.
(b) The total line inductance is L henries.
(c) When a voltage Vis applied to the line, a wave of this voltage travels down the
line.
(d) The voltage Vis accompanied by a current I.
159 The Detailed Points of Association

(e) When the wave reaches the end of the line it is reflected according to the
nature of the termination.
(f) At an open-circuit termination the current is zero, and the wave is reflected so
as to reduce the current to zero. Since energy is not lost, this implies that the two
electric fields reinforce to make the total voltage 2V.
(g) At a short-circuit termination, the voltage is zero, and the wave is reflected so
as to reduce the voltage to zero, and the two magnetic fields reinforce to make the
total current 2Z.
(h) The <strong>source</strong> of energy at the sending end of the line is ignorant of the nature of
the termination until the wave has travelled to the end and back. If the transit time
for the line is T seconds, this interval is 2T seconds.
Then the energy fed into the line in 2T seconds is VZ2T. In the open-circuit case
the energy on the line after an interval of 2T is 3C(2V)’. In the short-circuit case
the energy on the line after an interval of 2T is iL(2Z)’. So, since these three
amounts of energy are all the same,
VIT = CVz = LI’,
= /(;) and T = J(Lc).
whence
I
Length of the line
The speed of propagation is given by
T
The same technique, making similar assumptions, can be used to give the
velocity of propagation of other types of waves in other media: but the equations
are usually more complicated because the pressure-strain relations are less easy
to deal with.
11.5.5 Conclusion
The point of the above examples is to show that if the teacher of <strong>physics</strong> wants
mathematical backing for some of the newer topics now in the secondary-<strong>school</strong>
course, methods of dealing with the mathematics can usually be found that do not
make inordinate demands on the pupils, but which may yield patterns that are as
interesting mathematically as they are physically, so that cooperation is mutually
beneficial. Further examples wil be found in the Nuffield advanced-level <strong>physics</strong>
course, especially where the mathematical ideas behind the exponential function
are approached experimentally through work with capacitors and decay experiments
in radioactivity.
The scope for collaboration is considerable. Modern mathematics is clearly
here to stay and note should be taken of it by those doing curriculum reform in
<strong>physics</strong>. Perhaps it is not too much to hope that some day there may be a properly
integrated mathematics and <strong>physics</strong> programme.
160 Physics and Mathematics

I2 Physics and Computer
Education
The increasing importance of computers in the world today suggests that computer
education may have an important part to play in <strong>school</strong>s in the future. This wil involve
considerable links with <strong>physics</strong> education and some of these are discussed in this chapter,
which is largely contributed by Peter E. Dutton with some additional material from
David Chaundy. Consideration is first given to the hardware, and work with both logic
and analog circuits is discussed. Then the software is discussed. first from the viewpoint of
what programming might be done in <strong>school</strong>s, and secondly the applications and
implications of computer work.
12.1 Introduction
Most teachers wil have heard of computers, and some may even have used one.
All children wil have met them through their science fiction, whether on television
or in <strong>books</strong> and magazines. Computer is a word that may have considerable
emotion attached to it, if only because few people know what a computer
can do, and only very few have a clear idea of its limitations as well as its many
possibilities. This chapter is not written to add to the generalities, but aims to
summarize the situation facing <strong>physics</strong> teachers in <strong>school</strong>s.
If he has not yet got a clear picture in his mind, a <strong>physics</strong> teacher first needs to
distinguish between the two basic types of computer, namely the digital machine
working with discrete numbers (almost always in binary form) and the analog
device which usually makes a current or a voltage represent some other physical
quantity. Both may be general-purpose machines, but there are specialized
examples of both types and also of joint or hybrid machines.
The general-purpose digital computer has means of inserting a sequence of
instructions (or a program) which is stored in some convenient way. This can
then be obeyed automatically by the machine which wil act on some information
(or data) and produce results either to the operator or to another machine or
computer. The speed at which these instructions can be obeyed is usually extremely
high, and the accuracy of any calculation is only limited by the number of
significant digits capable of being held in one address of the computer’s store.
The general-purpose analog machine has usually to be set up to solve a particular
problem or series of problems. The setting up may take many days or
weeks; the calculation is virtually instantaneous, and the accuracy is decided by
the composite accuracy of the components of the machine.
161 Introduction

Digital machines tend to dominate the computer scene, and for this reason
most work at <strong>school</strong> level wil probably be on these devices. It can consist of work
on the electronics and/or the logical techniques that are incorporated in these
computers (the hardware side), or it can consist of using a digital computer in
some manner (the software side). On the other hand, analog equipment which is
cheap enough for a <strong>school</strong> can do a few jobs which do not appear trivial to the
pupils.
12.2 Hardware: work with logic circuits
Many <strong>physics</strong> courses in <strong>school</strong>s include some work on electronics. This may
concentrate on the physical explanation of the working of the components themselves,
with calculation or experimentation to determine the relevant characteristics,
and then the use of these characteristics to study the design and behaviour
of electronic devices using these components.
An alternative approach consists of using electronic ‘black boxes’ to undertake
certain tasks without inquiring too closely into the details of the design of
the insides of these boxes. This technique certainly enables students to perform
more work of an investigation or project nature within a restricted time, and it is
also similar to the way electronic engineers use integrated circuits which they
neither would nor could design. A very profitable <strong>source</strong> of such investigations is
the use of logic circuits to solve problems. A possible sequence of such directed
experiments might be to start with single AND and OR gates and their negations,
NAND and NOR. The next step would be to combine these to solve logical problems,
or to form additional gates such as EXCLUSIVE OR, half-adder and fulladder
circuits (Codling, 1966; and Kelly, 1969). This latter will need the bistable
circuit, so other astable or monostable circuits could be studied (Wray, 1970).
Finally, binary adders and/or shift registers, ring counters, etc. could be constructed.
This sort of sequence has obvious connections with the arithmetic unit
of a digital computer (Dalziel, 1967; Dutton, 1966 and 1968a; James, 1969; and
Ogborn, 1961). Some students might wish to pursue the idea further and investigate
or construct input and output techniques, memory devices or control circuits.
An alternative approach, though, is to use the logic gates in ‘control
situations’. This sort of course is being developed in the United Kingdom and it
would seem to have many possibilities in bringing into the classroom relatively
advanced technological ideas adapted for 13- to 16-year-old children. It also helps
to introduce pupils to the whole field of automation, process control and the use
of computers.
12.3 Hardware: work with analog circuits
Most <strong>physics</strong> courses in <strong>school</strong>s include some work on direct-current circuits,
and many concentrate on Ohm’s law, resistors in series and in parallel, and power
calculations. An alternative approach is to introduce the principles of analog
computing (although at elementary levels this is too grand a title). Consider the
162 Physics and Computer Education

i -
Figure 5
-
circuit shown in Figure 4: movement of the contact X can change the voltmeter
reading to a given fraction of the supply voltage. If two such potentiometers are
placed in tandem, a simple multiplication circuit is produced as shown in
Figure 5. However, this needs careful designing if it is to work with reasonable
accuracy, for the loading of the potentiometers wil alter the fraction of the voltage
available. There is plenty of scope for experimental and theoretical work
here. Multiplication by fixed amounts, or scaling, can also be introduced with
fixed-value resistors, and combining these ideas with the null-reading galvanometer
technique enables one to balance different ‘questions’ and ‘ answers ’, as
shown in Figure 6.
Because of the loading problem for any serious analog work one needs to use
high-gain operational amplifiers. With the availability of integrated circuits these
are now relatively cheap. One need not attempt to build a full-size analog computer,
for one can easily set up a series of directed experiments using simple
163 Hardware: Work with Analog Circuits

Figure 6
apparatus (Cumbers, 1969 and 1970, and Dutton, 1968b). As with digital work,
some pupils may become so interested and involved in this work that they wish
to build ‘proper’ analog machines.
With a simple machine using four operational amplifiers a pupil can solve the
first-order differential equation of exponential decay or exponential increase, or
the second-order differential equations of pulling under gravity with air resistance
and of simple harmonic motion With positive or negative damping. Though
it may be difficult to get accurate results on a simple machine, the work of translating
the problem into machine terms wil give the student considerable insight
into the meaning of differential equations. Furthermore, if the solution is displayed
on an oscilloscope with a slow time base, rapid events such as the motion
of a projectile can be seen in slow motion. Many examples of such work can be
found in literature (Durling, 1970; Hinson, 1968 and 1969; and Mackman, 1967).
12.4 Software: programming
A great deal is said and written about the introduction of computer education
into <strong>school</strong> curricula. When this has occurred in the past it has usually just been
the teaching of a particular programming language (usually Fortran or Algol),
and the running of a few pupils’ programs. Because of the nature of these two
languages, and probably mainly because the topic would be taught by members
of either the mathematics or science staffs, the problems tackled by the students
have been largely mathematical or scientific. For a pupil in his latter years at
<strong>school</strong> who is reading <strong>physics</strong> this has obvious advantages in that it helps to
prepare him for his move to higher education, whether he wil read <strong>physics</strong> there
or not. And even for those who do not proceed to college or university the
insight into scientific and mathematical programming may be extremely useful,
both in removing some of the fear and mystery often associated with the use of
computers, and also in giving relevance to different parts of the existing syllabus.
While this sort of work should be encouraged and extended to more <strong>school</strong>s, it
164 Physics and Computer Education

should not become the only element of the physicist’s computer education; the
ideas in the next section are extremely important.
For those who have not tried to introduce any programming into their work in
<strong>school</strong> there are several points to note:
(a) It is absolutely impossible to do any programming without adequate computing
facilities being regularly available for the students.
(b) These facilities should be geared to the running of a fairly large number of
short programs; for this reason it is advisable to use the services of computer
departments at universities, polytechnics and colleges rather than those in industry
and commerce. The latter are often unsuited to cope with this type of
work, for the departments are usually planned to run relatively few programs,
each of which may take a lot of computer time.
(c) When arranging facilities, remember the major problem may be the preparation
of the program into a form acceptable to the computer, i.e. the punching of
paper tape, cards, mark-sensing. teletypes, etc. It may be advisable to employ
professional data-preparation staff rather than to have pupils use the punches or
teletypes and have the majority of their programs rejected for punching rather
than program errors.
(d) The time taken between the student writing his program and receiving the
output from the computer, or turn-round time, wil vary coi?s;derably according
to the facilities being used. An on-line terminal directly connected to a large
multi-access machine wil probably produce responses fzster than the user can
use them; a postal or courier service to a computer depzitment that only affords
very low priority to the running of these pupil programs may mean a turn-round
time of several weeks. The time that is acceptable wil also depend on the type of
pupil writing the programs ; for a pupil aged between approximately thirteen and
fifteen who is just learning how to program the computer a turn-round time of up
to three days is probably acceptable when one remembers the pupil’s other
studies. For an older pupil who is still developing programming techniques a
turn-round time of up to twenty-four hours is probably acceptable. However,
for an older student who wishes to use the computer as part of his main studies
(for example, a physicist who wishes to process experimental data) a data-link
may become necessary. This should ideally be on-line so that the student receives
the responses from the computer immediately, but for financial reasons he may
have to accept an off-line mode of working with a turn-round time of between
one and three hours. Alternatively a relatively small, programmable desk-top
electronic calculator might suffice.
*
Once the arrangements for running the pupils’ programs have been made and
tested, the teacher wil have to plan his course. He wil have to choose the particular
language his pupils wil use, assuming that this is not decided for him by
the particular computing facility chosen. He can use a ‘low-level’ or a ‘highlevel’
language. The former is near to the particular coding that has been
developed by the manufacturer of the computer in question, and wil probably
165 Software: Programming

vary considerably from one machine to another (and certainly from one manufacturer
to another). It may use mnemonics rather than binary codes, but it will
require a lot of extremely careful study before any problems beyond the extremely
trivial are tackled. However, using this type of language does enable the
pupil to follow exactly how the computer works and so gives the future programmer
a better understanding of the requirements and limitations of high-level
languages, besides being extremely useful to a future computer engineer.
High-level languages have been developed to be, as far as is practicable,
machine independent, i.e. a program written in such a language will,with minor
alterations, run on any machine above a certain size. Such a program, called a
<strong>source</strong> program, has to be translated by the computer into its own internal coded
version, or object program, and this is done by a master program called a compiler.
So, in general terms, the computer will need to have sufficient storage space
to hold both the compiler and the object program it generates before the object
program can be obeyed. High-level languages, such as Fortran, Algol, Cobol or
Basic, have the advantage that they enable students to write programs very early
on in a course because of their similarities to English and to algebra. They also
enable interested students to tackle non-trivial problems, and are in fact used by
most computer professionals. However they do hide from the student the exact
way in which a computer works. None the less a high-level language can be
recommended for use in <strong>school</strong>s.
Once the language is chosen, the exact form of the course will depend on the
age and abilities of the pupils. Most programming courses will start with a
simple linear (i.e. non-branching) program such as the conversion of a measurement
in one unit to another, a sum of money in one currency to another and so
on. This may be followed by formula-substitution problems, with many examples
readily available to the physicist. The logic and control of a looped program may
then be tackled, and this may lead into the use of arrays or subscripted variables.
With these powerful techniques pupils may produce graphical solutions of
their problems, calculate the electrical energy of an ionic crystal, obtain numerical
solutions of Schrodinger’s equation or perform numerical integrations using
Simpson’s rule. Those studying biology may use the computer for statistical calculations,
while others may prefer purely mathematical problems such as finding
prime numbers, the summation of infinite series, the calculation of e or K to 200
significant figures.
It is suggested, however, that at least one non-mathematical problem be
tackled if the available time permits. Examples may be found within the <strong>school</strong>
(for example preparing class lists, calculating the age of a pupil or finding the day
of the week on which he was born, listing pupils with the same first name, listing
pupils by areas of residence, by parental occupations, by pupils’ hobbies, etc.).
Other examples may be found outside the <strong>school</strong> in commerce and industry.
Several schemes of providing such outside links have been tried.
166 Physics and Computer Education

12.5 Software : applications and implications
It is agreed that the applications and implications are by far the most important
part of computer education for the future, whether it is for <strong>physics</strong> pupils or for
those working in other disciplines. While one can hope that the plans being proposed
for ‘computer education for all’ wil be implemented in the majority of
<strong>school</strong>s within the next few years (British Computer Society, 1970; and Scottish
Education Department, 1969), the majority of pupils wil only become aware of
computing by its applications in their daily lives. The implications of this work
are vast, and need to be understood by the population as a whole if the worst
features of another industrial revolution are to be avoided. Exactly how this aim
can be achieved wil depend largely on the country, the type of <strong>school</strong> and the
availability of suitably trained and interested teachers.
Here the physicist could play an important role because of the nature of his
work and training. A physicist is familiar with mathematics and also with engineering,
including the human, social and economic problems associated with it.
This places him in an important central position when it comes to effecting the
changes in <strong>school</strong> curriculum proposed above. A <strong>physics</strong> teacher may be better
able to introduce these changes than his mathematics or economics colleagues.
Because of his background and training a physicist wil need to acquaint himself
with as wide a range of computer applications as possible. These can be summarized
under one or more of the following headings :
(a) Mathematical calculation : for example, the detailed analysis of a given problem,
whether it is the flight of a space probe, the path of a subnuclear particle
through a bubble chamber or the calculation of bending moments for a bridge
member.
(b) Simulation problem: for example, the working of a logical or mathematical
model of a situation which has so far defied attempts at rigorous and detailed
mathematical analysis, or of a situation in which the economic advantages of
simulation outweigh the greater accuracy of analysis.
(c) Sorting problem : for example, the large part of data-processing techniques.
Often information held in one file is to be merged with new data, and a new file to
be prepared for subsequent use. Management may require certain information
from many such files, and this has to be arranged in such a way that appropriate
decisions can be taken.
It is much more difficult for teachers to become aware of the implications of the
use of computers, and this is an extremely difficult idea to teach in a formal way
in <strong>school</strong> or elsewhere. Perhaps the only possible answer wil be for <strong>physics</strong>
teachers to join with their colleagues in other disciplines, in particular those
specializing in the humanities, and attempt to discuss the problems as a team
with their pupils. In such team-teaching efforts the physicist could play a useful
part if he were willing to share his appreciation of the applications under discus-
167 Software: Applications and Implications

sion with the whole group, and to join in the wider philosophical discussions that
could ensue. One such problem that has proved to be a useful starting point is the
possible use and abuse of large ‘data-banks’ that are being proposed by certain
computer professionals. Teachers wil probably have to look to universities,
however, for guidance with this sort of work (George, 1969).
168 Physics and Computer Education

Part Five
Learning Re<strong>source</strong>s

13 Physics Apparatus
This edited chapter is based on contributions provided by G. C. Norman, Patrick Whittle,
R. F. Melton and John Lewis, all of whom have been concerned in the development of
apparatus for new programmes. The chapter begins with some general principles about
apparatus and concludes with detailed information which it is hoped wil be of use to
others, especially in developing countries.
It should be stressed at the outset that it is with the needs of secondury education in
mind that this chapter has been written. The warmest tributes can be paid to those
involved with new programmes forprimary education where the very simplest of local
re<strong>source</strong>s have provided the necessary apparatus, but the needs of secondary education
are a little more sophisticated. The view expressed in this chapter is that the maximum use
must be made of local re<strong>source</strong>s, even at this level, but equally that <strong>physics</strong> at this level
cannot be taught without adequate apparatus, especially if the pupils are themselves to be
involved in the subject. It is most important that national authorities should appreciate
the essential need for providing apparatus, from whatever <strong>source</strong>, if <strong>physics</strong> is to be taught
in the manner indicated throughout this volume.
13.1 Two notes of warning
It would seem appropriate to begin this chapter with two warnings.
(a) Apparatus is an essential part of <strong>physics</strong> teaching and the development of
apparatus suitable for the programme wil be a necessary part of curriculum
reform. Enthusiasts with the skill to devise experiments and to develop apparatus,
both simple and complex, play a vital role in any new project. But the
apparatus must not be allowed to dictate the general policy of the project. It is a
little too easy for physicists to be carried away with enthusiasm for a particularly
neat way of doing an experiment and to assume it must be incorporated in the
programme.
One is reminded of C. P. Snow’s Science and Government where he describes
the single-minded scientist who, flushed with success in one particular field or
with the operation of one particular piece of apparatus, takes too narrow a view.
C. P. Snow calls these men ‘gadgeteers’ and he writes about the ‘euphoria of
gadgets ’ :
171 Two Notes of Warning

. . . Any scientistwho is prone to these euphorias ought to be kept out of government
decisions or choice-making, at almost any cost. It does not matter how good he is at his
stuff. It does not matter if the gadgets are efficacious, like the atomic bomb, or silly,like
Lindernann’s parachute mines for dropping on air screws. It does not matter how confident
he is; in fact, if he is confident because of the euphoria of gadgets, he is doubly
dangerous. The point is, anyone who is drunk with gadgets is a menace. Any choice he
makes, pahicularly if it involves comparison with other countries, is much more likely to be
wrong than right. The higher he climbs, the more he is going to mislead his own country.
The nearer he is to the physical presence of his own gadget, the worse his judgement is
going to be. It is easy enough to understand. The gadget is there. It is one’s own. One
knows, no one can possibly know as well, all the bright ideas it contains, al the snags
overcome.
Not everyone agrees with C. P. Snow, and in any case he is referring above to
much wider issues of scientists in government, but his remarks are applicable to
curriculum reform in <strong>physics</strong> and should be heeded by those responsible for it.
One can see this at a very mundane level: ripple tanks for studying wave phenomena
abound throughout the world in the new programmes: the ripple tank
used by P S S C, the one developed for the Unesco Sao Paulo <strong>physics</strong> project, the
various types designed for use with the Nuffield programme, the sophisticated
and efficient ripple tanks from Leybold and Phywe in the Federal Republic of
Germany, and the one developed in the Israel Science <strong>Teaching</strong> Project. As
Snow says, any choice to be made, ‘particularly if it involves comparison with
other countries’, is easily clouded by other considerations. The truth is that all
the above ripple tanks are good for the particular purpose for which they were
designed, and any attempt to say which is best is meaningless.
The above comments should not be taken to decry the immense contribution
that the ‘gadgeteer’ has to make to the reform of <strong>physics</strong> teaching. If he is wise
the leader of any project wil give the gadgeteer in his team every possible encouragement
and be generous in praising the products of his skill and ingenuity :
many a project owes much to the contribution made by a particular kit of apparatus
to the good teaching of a topic. The warning is merely that the tail must not be
allowed to wag the dog.
(b) The second warning is quite different, but also fundamental. Physics is an
experimental science and much stress has been laid in this volume on the importance
of getting children personally involved so that they come to understanding.
Personal involvement means doing experiments themselves, and doing experiments
implies the need for apparatus. This need to provide apparatus cannot be
overlooked by national governments wishing to improve the quality of <strong>physics</strong>
teaching.
Apparatus does not have to be sophisticated, in fact the simpler the better.
Isais Raw has shown what can be achieved with the simplest apparatus in
Brazil and there is no doubt at all that, at the elementary level, a great deal of
<strong>physics</strong> can be learnt using the most simple of local re<strong>source</strong>s, pieces of wood, tin
cans, stones and string. But this volume is concerned with <strong>physics</strong> education at
the secondary level. It must be accepted, for example, that electricity cannot be
172 Physics Apparatus

taught at this level merely with a blackboard and chalk. especially to children in a
developing country who may come from a village background where the uses of
electricity are relatively unknown and where the child lacks the experience of his
opposite number in more technologically sophisticated countries. Nor is the
situation met by the provision of a set of transparent slides, however well produced.
Without personal involvement the teaching is merely likely to encourage
an awe of <strong>physics</strong> rather than something to be understood as a reality which can
affect their lives. A country which starts by saying that it is a poor country which
cannot provide apparatus and needs supplies of paper cut-out models to illustrate
principles should probably not attempt to teach electricity at all in its
secondary <strong>school</strong>s.
The nature of <strong>physics</strong> is such that some apparatus is essential for its teaching.
It is up to the 'gadgeteers' to ensure that what is provided is as simple as possible,
and it is necessary for the government agencies, whatever they may be, to be
warned that the provision of apparatus is vital to <strong>physics</strong> teaching.
13.2 Cutting coats according to the cloth
The full Nuffield 0-level <strong>physics</strong> course, intended for the academic streams of
secondary <strong>school</strong>s in the United Kingdom, requires in the later years of the
course some sophisticated apparatus such as extra-high-tension power supplies
giving 0-5000 volts continuously variable, scalers which can be used as a standard
clock timing to 1/1000 second and also for radioactive work, and special
thermionic emission tubes and oscilloscopes. both for pupil use and for demonstration
purposes. This apparatus is justifiable for the purpose for which the
course was written, and its provision has been just (if only just) within the grasp
of the <strong>school</strong>s for which it was intended. The use of these relatively sophisticated
items however does not imply that they are either necessary or desirable in a new
programme in a developing country. If a sophisticated experiment is required as
an essential part of a course, it may be economically more sensible to put the
experiment on film and make the film generally available.
Some of the finest apparatus for use in <strong>physics</strong> teaching to be found anywhere
in the world is made in the Federal Republic of Germany. Its use may be right for
some countries, but it is certainly not right in the economic circumstances of
some developing countries.
It is essential therefore that in designing apparatus for a new programme the
coat should be cut according to the cloth available. Furthermore, as stressed
elsewhere in this volume, it is important that the ultimate implementation of the
programme be remembered throughout the stage when apparatus is being developed.
It may be possible to provide a certain piece of apparatus to all the
<strong>school</strong>s involved during the trial stage, but if the cost is such that it wil never be
possible to provide it for every secondary <strong>school</strong> in the country using the programme.
then the effort is to no avail. For these reasons, not only must the coat
be cut according to the cloth, but as far as possible the cloth should be based on
local re<strong>source</strong>s. This wil be discussed further in this chapter.
173 Cutting Coats according to the Cloth

Before discussing the problems which are peculiar to developing countries, it
would seem wise to look at present trends in <strong>physics</strong> apparatus in more technologically
advanced countries.
13.3 Apparatus for teaching <strong>physics</strong>
\
It is generally agreed that it is desirable, whenever possible, to get pupils to do
experiments themselves in order to give them first-hand experience, so that they
get the feel of science and learn to find out for themselves. ‘Hear and forget, see
and remember, do and understand’ is widely accepted as the ideal for <strong>physics</strong>
teaching. For this to be achieved, apparatus for pupil experiments must be available
in large quantity. Whenever feasible, experiments should be done as class
experiments with the pupils working individually, in pairs or at most in groups of
four.
There are two reasons why this is not always practicable, and on those occasions
a demonstration experiment should be shown instead. Sometimes the
apparatus needed is too expensive (occasionally too delicate) for the <strong>school</strong> to
have it in quantity, and the experiment must necessarily be done by the teacher.
The second reason is the time factor: if the pupils did every experiment themselves,
it would not be possible to complete certain courses.
Sometimes of course the apparatus, even for a single demonstration, is still
too expensive, or the experiment may take too long to perform. On these occasions
it is necessary to resort to film: see a fuller discussion of this in the chapter
on audio-visual aids (chapter 15). On the other hand films should not be allowed
to become a substitute for live demonstrations or a cheap way to avoid buying
apparatus. This sequence (failing class experiment, demonstration; failing
demonstration, film)is widely used in new programmes, though of course very
different from the German tradition where the demonstration experiment is
dominant; it is equally different from the American PSSC scheme where for
various reasons the middle stage of demonstration plays a very small part.
Such a policy conditions the kind of apparatus that is needed and is discussed
below.
13.3.1 Demonstration apparatus
Demonstration apparatus must necessarily be different from apparatus for pupil
use: it must be large enough to be seen by the class as a whole. An ammeter for
pupil use, for example, is normally relatively small with scales in a horizontal
plane, while a demonstration meter must be considerably larger with scales in a
vertical plane for group observation.
There is an important principle about versatility in demonstration apparatus
which has come to be generally accepted. Versatility in apparatus design is both
economically desirable and educationally sound. There was a tendency at one
time for manufacturers to make an item complete in itself, to be used for one particular
purpose only. This makes apparatus expensive and is not therefore the
best way of providing the teacher with the equipment he needs for good teaching.
174 Physics Apparatus

-*:-<
Figure 7 Demonstration meter and student ammeter
It is better to provide versatile, general-purpose apparatus which has many
different uses. For example, a general-purpose power supply and a generalpurpose
amplifier. both of which can be used in a large variety of different experiments,
are more economical than having to build a power supply and an amplifier
into every piece of apparatus requiring such units.
‘Special’ apparatus which wil do one job only is not viewed with great
enthusiasm, especially if it is expensive. A scaler for radioactive work might be
hard to justify for radioactive work alone, but if it incorporates a 1000 Hz
oscillator, so that it can be used as a millisecond clock, then this versatility justifies
its purchase.
Contemporary techniques have now become commonplace in the demonstration
apparatus being used in the more technologically advanced countries. In
traditional courses in those countries such devices as Attwood’s machine and
Fletcher’s trolleys were used. These were remarkable devices in their day,
developed because of the difficulty of measuring time in <strong>school</strong> laboratories. W e
can pay tribute to Attwood’s ingenuity but there is no place for his machine
when electronic equipment enables us to measure time more precisely and thereby
to measure the acceleration due to gravity much more directly. Electronics has
become a valuable tool in our teaching. A scaler which incorporates a 1000 Hz
oscillator enables us to measure time to a thousandth of a second and helps the
pupil to understand the principles involved much more readily than ever he
could with Attwood’s machine.
175 Apparatus for <strong>Teaching</strong> Physics

Friction was another problem in classical apparatus and so many corrections
had to be made that some pupils missed the simple principles one hoped to
illustrate. They were told that Newton said that when a body was given a push it
continued to move in a straight line, but their experience told them that it always
came to rest! The use of solid carbon dioxide pucks (in which the pucks float on a
cushion of gas on a large glass plate), together with linear air tracks and even air
tables (in both of which the vehicles float on air from a blower), have changed all
this. With these devices friction has ceased to be the problem it once was and
the <strong>physics</strong> is much more readily understood by the pupils.
There are many examples of this kind of development. Centimetre waves, used
for radar, have a much more convenient wavelength than that of light in the
teaching of wave phenomena, which consequently becomes easier and more
direct. Hall-effect probes can transform the teaching on magnetic fields. There
are more and more advocates of gas lasers for <strong>school</strong> teaching and the cost of
such lasers continues to fall as the demand for them increases.
These changes can also affect elementary teaching. A study of Boyle’s law has
for long been included in <strong>school</strong> courses. In the traditional apparatus the volume
of the gas was related to differences in height of mercury columns, which in turn
were related to pressure. This was satisfactory for the bright pupil who could see
the relation between pressure and volume, but for the less bright the <strong>physics</strong> was
far less obvious, being obscured by the columns of mercury in the midst of the
argument. It is much simpler if Bourdon gauges are used to measure pressure, so
that the pupil can see directly the relationship between pressure and volume.
Above all,there is the oscilloscope. There is perhaps no <strong>physics</strong> laboratory in
the world without an oscilloscope. What about <strong>school</strong>s? There was often one
oscilloscope used for demonstration, but their design has changed radically since
the war. Good oscilloscopes, costing only &20, or under $50, are now available
for pupil use. These can make much difference to teaching. The value of the
oscilloscope in more advanced work in secondary <strong>school</strong>s needs no advocacy; its
use is almost unlimited.
There is another principle here. Industrial oscilloscopes have long been available,
but they are not always suitable for <strong>school</strong> purposes. Something less
sophisticated, with fewer knobs, may be much more suitable for <strong>school</strong> purposes;
technological countries surely have a duty, both to themselves and to developing
countries, to do all they can to see that the right kind of commercial apparatus is
made available for educational purposes.
13.3.2 Standardization
It would be a great help to <strong>physics</strong> teaching throughout the world if there was a
greater measure of standardization over equipment. It is too much to expect that
plugs and sockets could ever be standardized, not least when the ax. mains
voltage is not standardized. But a great deal could be achieved if demonstration
apparatus, for example, adhered to standard size fuses. Most European countries
are now standardizing on 20 mm cartridge fuses and if these could be confined to
176 Physics Apparatus

preferred ranges 50 mA, 100 mA, 250 mA, 500 mA, 1 A, 2 A, 5 A, it would make
the situation much easier in developing countries where replacement of fuses can
be a serious problem, especially in <strong>school</strong>s.
In European countries there is also a measure of standardization of terminals
for connecting pieces of sophisticated apparatus: 4 mm sockets have become
standard, and leads with 4 mm plugs have replaced the tedious business of baring
copper wire. It would be a good thing if agreement could be reached on coaxial
plugs and sockets, the sizes of retort-stand rods, sizes of pressure tubing, glass
tubing and so on.
13.3.3 Appnratzrs for pupil experiments
All the new science-teaching programmes accept the principle that understanding
comes through the pupils doing experiments themselves. Talk and chalk alone
give little feeling for science, encouraging an authoritarian factual approach.
Good demonstrations by the teacher may enhance the reputation of the teacher,
but it is only when pupils come to handling the apparatus that they really accept
the phenomenon concerned. The knowledge acquired in this way is something of
their own, no longer something second-hand. To quote one very simple example,
it is easy to discuss at a blackboard the charging of a gold-leaf electroscope by
induction, but this lacks reality until the teacher demonstrates it. Even then the
phenomenon is not part of the pupils’ own experience, but if each pair of pupils is
provided with an inexpensive electroscope, a polythene rod and a cellulose
acetate strip, they wil gain a much better understanding.
In general, for pupil experiments the apparatus must be simple and inexpensive:
in some cases so inexpensive that it is almost expendable.
Kits of simple apparatus have been developed in various parts of the world : in
the PSSC project in the United States, in the Unesco project in Latin America,
in the Nuffield projects in the United Kingdom, in East Africa, in Israel, to
mention only a few.
It is perhaps unfortunate that the name kit has been used for these units. The
word is often associated with model aircraft kits for children, but a good apparatus
kit is certainly not an assembly kit. It is a collection of apparatus which enables
a large number of different experiments to be done. What are the characteristics
of a good kit? It should include sufficient apparatus to enable pupils to
work in pairs or small groups on a particular series of experiments. In general.
two pupils working together get the most out of the apparatus. They can discuss
it together and their ideas react on each other so that they make rapid progress.
Furthermore a good pupil may encourage a weaker one. On the other hand. if
three pupils work together on an electromagnetic kit motor, for example, one of
the three may easily become a spectator whilst the other two do all the investigating.
Occasionally cost, as well as space and convenience in a laboratory, may
require three or even four pupils to work together, as for example with rippletank
kits. There is a limit to the number of such ripple tanks that can be used at
any one time in a laboratory, and luckily the experiments are such that little is
177 Apparatus for <strong>Teaching</strong> Physics

lost if three or even four pupils work together on one ripple tank. However,
working in pairs is considered the ideal arrangement.
A good kit is a versatile kit, capable of a large number of different experiments.
To quote one example, some forty or fifty different experiments canbe done with
the electromagnetic kit used in the Nuffield programme : it provides sufficient
material for work lasting for half a <strong>school</strong> term. Such a kit is simple and the individual
items are all low cost, expense merely arising from the need to provide
each item in sufficient quantity.
At one stage in the development of the Nuffield courses some manufacturers
attempted to provide ‘improved’ versions of the electromagnetic kit with the
coils already wound and ‘efficient’ commutators already attached. These ‘ improvements
’ merely turned the kit into an assembly kit and defeated the purpose
for which they were designed. So much more is learnt when the pupils make their
own commutators; they learn by their own mistakes. A coil already wound stops
the pupil from wondering what would be the best number of turns.
Kits can vary considerably in the different skills they are trying to teach. The
Nuffield electromagnetic kit referred to above does aim to develop some manipulative
skill, which it was felt should be part of that particular course, as well as
the principles of electromagnetism. Earlier in the Nuffield course, when electric
currents were first being studied, it would have been possible for the pupils to
wire up all their own circuits. At that stage the screwdriver and the wire strippers
might easily have dominated the work, and the principles of electric circuits
might not have been appreciated as they can be by the use of the Nuffield circuitboard
kit in which the circuits are put together on a board using specific fixed
components. The principles of circuitry (the effect of varying the number of cells
or the number of lamps, the arrangement of the lamps, the uses of variable
resistances, fuses, rectifiers and meters) are much more readily understood at that
stage if manipulative skills are not being taught at the same time.
In developing kits of apparatus for any course anywhere it is important to
think out in advance exactly what the apparatus is intended to do and the skills it
should be developing.
A warning however comes from East Africa :
If apparatus is to be successfully handled by secondary-<strong>school</strong> pupils, it must be simple to
manipulate and should lead as directly as possible to the concept being developed, criteria
which are not always satisfied by equipment of simple design and cheap construction. To
take two examples; it is much easier to draw valid conclusions from ‘balancing’ experiments
if the weights used are adjusted to be fairly accurately equal (and therefore more expensive
or difficult to produce locally) than if, say, nuts having a variation in weight of
*lo% are used; commercial moving-coil galvanometers are much easier to use than
equally sensitive, and cheaply made, fibre-suspended moving-magnet instruments.
This is a reminder that costs must not be kept so low that the apparatus fails
to do effectively what is required of it.
178 Physics Apparatus

13.4 Problems peculiar to developing countries
The majority of developing countries have inherited science courses which originated
in other nations, and not unnaturally science teachers responsible for
ordering equipment usually imported apparatus which was manufactured and
had already proved satisfactory in the country of origin of the syllabuses and
examinations. When these teachers were expatriates, there was an added tendency
to choose items with which they were familiar from their own background.
Even when local curriculum development is taking place, in the first stages it is
common practice to begin limited trials with experiments and apparatus designed
overseas but to be assessed in the local situation.
It would clearly be foolish for reformers to ignore completely either the equipment
already in the <strong>school</strong>s or that recently developed for similar purposes
elsewhere. No single country can ever hope to produce a completely new <strong>physics</strong>
course tailored perfectly to its own requirements with entirely new sets of apparatus
and teaching aids; the cost in terms of finance, time and manpower would be
enormous, and the desirability of being entirely different from the rest of the
world is somewhat questionable! However, that a demonstration is effective in
Canada or Sweden does not mean that it wil be suitable for teaching in Malawi
or Singapore; the age, background and outlook of the teachers and pupils wil be
different, the <strong>school</strong>, laboratory and physical environment wil be different and
the aims and requirements of the course and educational system may be quite
different from their counterpart elsewhere.
A notorious example is Hope’s experiment for measurement of the temperature
of maximum density of water, which for many years appeared on examination
papers taken by candidates in the tropics. Most <strong>physics</strong> teachers gave up
trying to carry out the actual experiment, which is very difficult at high ambient
temperatures, while most pupils failed to see the point of the demonstration
as they were frequently quite unfamiliar with the process of freezing water.
Although this may seem an extreme example, Hope’s apparatus remains on
the shelves of many <strong>physics</strong> laboratories in the tropics bearing silent testimony
to this sort of mistake, which it would be all too easy to repeat by importing
new items of equipment which are attractive because they are modern, but which
may be equally inappropriate.
A recent example is the new Nuffield Boyle’s law apparatus incorporating
a Bourdon gauge which gives a false reading at any appreciable altitude above sea
level. This particular error may be corrected, but sometimes it is not possible to
make corrections when quantities of unsatisfactory apparatus have been imported.
It is therefore vital that each country or region should have some advisory
body or centre which can make recommendations about the most suitable
materials for teaching <strong>physics</strong> in that area; and there must be a means for making
this information known to the <strong>physics</strong> teachers themselves, who should of course
be represented on such a body, at least those in close touch with practising
teachers, such as lecturers in departments or colleges of education. The most
important type of apparatus, that to be used by the pupils themselves, should
179 Problems Peculiar to Developing Countries

e tried out in the <strong>school</strong> situation where, if it is going to break or prove useless,
it wil do so.
Apparatus for class experiments must not be too sophisticated for the average
pupil in a developing country, for although some wil be able to manipulate it
and see its significance there wil be many, from rural areas or poor homes, who
will not have at their disposal the practical skills and technical knowledge which
can often be taken for granted in the more technologically advanced nations.
Consequently, an experiment such as the microbalance, which is ideal for the
P S S C or Nuffield Physics programmes, may prove unsuitable for pupils elsewhere
because it is too difficult for them to manipulate. It may have to be replaced
by a less sensitive form of balance, more obviously useful in the eyes of a
pupil who is not sure why he should weigh a hair anyway. Again, while a laboratory
full of black boxes may be impressive, the boxes may in fact be less useful
than some simpler locally made equipment when one weighs up the actual understanding
of physical principles; there is little doubt about which wil be less costly.
It is unlikely that any <strong>physics</strong> programme can be devised so as to dispense
entirely with instruments of fairly sophisticated construction while at the same
time giving pupils a broad insight into the subject, especially at the higher levels
of the secondary <strong>school</strong>. Nor is it likely that such instruments could be produced
economically in the developing countries, bearing in mind the limited quantities
required and the acute shortage of skilled manpower and technical re<strong>source</strong>s.
There must, therefore, be some reliance upon imports and the aim should be to
keep these to a minimum so that best use can be made of available funds.
Multipurpose items, referred to above, offer an obvious economy and there is
more opportunity for their introduction when a new curriculum is being devised.
The general purpose pegboard stand of Introductory Physical Science is an example.
But care must be taken to ensure that the result of trying to make something
universally useful is not to make it inadequate for some specific purpose.
Durability is essential. For use in tropical climates ferrous metals should be
avoided where possible, or else protected by plating or paint; adhesives and
electrical insulation must be resistant to continuously high temperatures and
humidities ; insects must at all costs be prevented from entering instrument
casings.
Where equipment is in short supply it is likely to have very heavy use, and overworked
teachers, often in shorter supply than their equipment, should not have
the burden of frequent ordering of replacements (and of convincing fiscal authorities
that such replacements are necessary).
13.4.1 More sophisticated apparatus
It is agreed that simple apparatus should be used whenever possible, such things
as elaborate optical benches having no place in a <strong>school</strong> laboratory course. But
there is likely to be a need, especially in the later stages of secondary education,
for specialized instruments of some complexity. Under this head might be considered
such things as vacuum pumps, power packs, sensitive galvanometers,
180 Physics Apparatus

multirange meters, oscilloscopes, amplifiers, scalers for radioactive work, resistance
boxes and audio-visual equipment (whose maintenance may fall on the
<strong>school</strong> <strong>physics</strong> department even if it is used mainly by others).
In choosing between similar equipment made by different manufacturers,
priority should be given to the one for which genuine servicing facilities are
offered locally, if this applies at all. But it is advisable to check on a local agent’s
claim to provide service; this may only mean that he wil send it to the country of
origin for repair. In the absence of a repair service the existence of a local agency
is as likely to be a disadvantage as anything else, serving only to increase delays in
communication with manufacturers or to increase prices.
There is a strong case for standardizing on a national basis so that all <strong>school</strong>s
use the same model of a particular piece of apparatus. This would encourage the
manufacturer to establish a spares-holding agency or make it possible for an
official institution to carry a stock of spare parts. It would at least make the
teacher’s task of maintenance easier, as faults can be located more readily by
comparison with a similar, working, model borrowed from a neighbouring
<strong>school</strong>.
Manufacturers’ and suppliers’ specifications often fail to quote essential information
such as details of fuses and other replacement parts and of types of
connector required. These should be ascertained before purchase so that compatible
parts can be ordered at the same time. For the same reason it is advisable
to note this information while the equipment is new. Where repair kits are offered,
for example for light-beam galvanometers, they should be ordered with the
equipment to facilitate repair of transit damage without lengthy delays or risk of
further damage in returning it to the manufacturer.
The only real solution to the probiem of the repair of laboratory (and audiovisual)
equipment in less technologically developed countries is the establishment
of an officially backed servicing organization. which could also deal with
non-educational apparatus if this were necessary for viability. Standardization
of models would make it possible to hold a number of complete units in reserve
for loan when major repairs were needed.
13.5 Apparatus and curriculum development
Apparatus and curriculum materials are best developed side by side. In developing
the curriculum one determines the various fundamental objectives of the
programme, and it is possible to spell out the concepts to be studied; but the
exact method of achieving this cannot be indicated without a knowledge of the
apparatus that can be produced locally on an economic basis. It might be possible
to put over a simple concept in gravitation just as well with a stone and a
piece of paper as with a special vacuum tube. and it is invaluable for writing teams
to be sufficiently involved in apparatus development.
181 Apparatus and Curriculum Development

13.5.1 Where to begin
The first essential of apparatus and curriculum development is to ensure that
those involved are fully exposed to current developments in other countries.
This ensures the local programme is planned in the light of up-to-dat experience.
Such exposure can be obtained abroad, but a most valuable exposure programme
could be realized locally. Re<strong>source</strong> materials from various programmes could be
gathered together, preferably in a pre-service training centre, so that apparatus
and curriculum developers could study a series of programmes given by specialists
from the respective curriculum projects. Exposure would be based on actual
experience with the new curriculum materials, thereby illustrating the various
methodologies by actual involvement. Exposure could well be spread over twelve
months.
(The advantage of giving such exposure locally would be that the same
materials and courses could subsequently be utilized in regular pre-service
training, possibly leading to a M.Ed. degree. A natural part of such a degree
course would be thesis work involving comparative studies of specific topics and
methods of treatment under different programmes. This would automatically
lead to the development of new materials for the local curriculum, and act as a
continuous feeder to the needs of apparatus and curriculum development.)
13.5.2 Development stage
Curriculum development is usually achieved by attacking the problem, grade by
grade, within a general framework. Those involved with apparatus should consider
the course as a whole: it is wasteful if a piece of apparatus developed for a
lower grade proves inadequate for a higher grade and something extra has to be
produced.
Carefully controlled development is essential. New apparatus cannot be distributed
throughout a country at one swoop, however impatient ministries may
be, without first testing in trial <strong>school</strong>s. It is important to learn whether students
can handle the apparatus provided. The fact that a highly qualified teacher finds
a piece of apparatus convincing is no reason why a much less adept student
should be equally impressed. It is equally important that apparatus should be
tested for durability in the hands of students, and under local climatic conditions,
and large-scale production should take the findings of such trials into
account. The most important point to remember is that the success of any new
programme must be measured in the classroom by its impact on the students.
Feedback is essential and requires considerable integration of effort to control
the variable factors. Technicians must be trained in production techniques.
Laboratories must be improved to ensure full use of apparatus provided, while
teachers must receive adequate exposure to new materials and techniques.
A simple flow diagram illustrating the various stages of a typical programme
from the initial exposure to other programmes to the large scale adoption of the
new one is shown opposite.
182 Physics Apparatus

1 Pre-service
2 Developmenl
exposure
n
courses
curriculum development
3 Small scale
teachers, technicians
and administrators
4 Small scale
J. .L
<strong>school</strong> trials and feedback
5 Large scale
in-service training for teachers,
technicians and administrators
6 Large scale
I adoption of programme in <strong>school</strong>s 1
13.5.3 Use oflocul materials
When the apparatus requirements for new <strong>physics</strong> programmes are being drawn
up. the over-riding factor is inevitably the cost, and any economies which can be
made are welcomed. In practice there are often several, or even many, items of
equipment which would be highly desirable but which have to be eliminated
from the programme because of their expense : oscilloscopes, electron tubes,
power supplies, for example. However, the cost of class-sets of smaller items of
equipment mounts up to a comparable figure, and if economies can be effected
by local construction of these the money which is saved can be put to good use to
183 Apparatus and Curriculum Development

purchase some of the larger items which cannot easily be made locally. Most
teachers balk at the idea of making their own equipment, certainly in any quantity,
but most have one or two ideas of their own for apparatus which they have
made up and which show their use of local materials.
The greatest economy which can be made in the construction of <strong>physics</strong> apparatus
in developing countries is in the use of cheap materials, such as wood
which is readily available and easily worked, and of imported goods which are
widely used domestically or commercially. Economies in design can be effected
by simplifying and reducing apparatus to the basic essentials required to teach
the topic effectively, and often more effectively, to the unsophisticated pupil.
And it should not be forgotten that sometimes components can be imported in
large quantities at a cheap rate, and if the assembly of equipment can be done
locally, further savings can be made. Traditional <strong>source</strong>s must not be slavishly
used if suitable cheap alternatives are available.
13.5.4 Use of local experience
Insufficient attention is often given to the fund of experience which already
exists in many developing countries; new teachers, new <strong>school</strong>s and even new
pupils could benefit greatly from ‘the knowledge already gained by previous
<strong>physics</strong> teachers. This is invariably due to the lack of documentation of work and
lack of channels of communication between teachers, but this need not continue
where ministries and educational authorities are aware of the advantages of
using their local re<strong>source</strong>s.
No <strong>physics</strong> teacher, or group of teachers, in a developing country should ever
struggle on alone in an effort to improve local apparatus supplies without consulting
local inspectors, education officers or institutes and colleges of education.
There may well be other individuals known to them who have similar interests
and when they work together there may be sufficient progress for the activity to
warrant official backing.
Where a science teachers’ organization already exists there may be a forum for
the exchange of ideas for improvisation of equipment, and out of members’
exhibitions or suggestions may spring excellent local forms of apparatus which
can be developed to fit into the new <strong>physics</strong> programme.
13.6 Local production of apparatus in developing countries
The greatest need in local development of apparatus is flexibility of mind; the
greatest danger the slavish imitation of apparatus developed for use in technologically
developed countries. It may have been better in America to use one
kind of wheel on dynamics trolleys; it may have been better to use glass lenses in
England. Such wheels and such lenses may have been readily and cheaply available
in those countries, but it may be much wiser in a developing country to use
an entirely different kind of wheel and to overcome the problem of friction by
reducing the weight of the trolley; it may be better to use lenses and prisms made
184 Physics Apparatus

of plastic instead of glass since they may not only be readily shaped under local
conditions, but also be much cheaper. One programme may have used tickertape
timers which are operated from the a.c. mains because the necessary voltage
supply is readily available, but it may be better for another to use bell-mechanisms
operated from a battery. It is not a question of one design being superior to
another; it is merely a matter of which is more convenient and economical in the
local circumstances.
There are the classic cases of a developing country importing at considerable
expense dried seaweed of a particular type from England, because it was specified
in a particular biology programme, when the coastline of that country is covered
with another type which could just as well be used with some slight modification
to the programme; in another country there was the big import of dogfish
because they were specified in an examination syllabus, whereas another fish
might easily have been substituted. In <strong>physics</strong> there are instances of wooden
blocks being imported from overseas, made of timber which was initially exported
by the country concerned to the overseas manufacturer!
There are many developing countries which wil have to continue to import
certain items, particularly electrical or electronic equipment. What is needed is a
very careful reappraisal of what it is essential to import and what can be improvised
locally. There is scope for the import, not of finished items, but of certain
parts which can then be made up locally.
Work on this is most appropriately done at the curriculum development centre
where workshop facilities should be available. It is advisable to have a full-time
worker to man such a workshop, particularly in <strong>physics</strong> for which the apparatus
requirements are heavy, and he wil normally work in close touch with other
members of the <strong>physics</strong> panel investigating the new programme, while other
teachers can have access to his facilities. This last point is important, for it would
serve no purpose to produce highly developed items of equipment which prove
irrelevant to the needs of the <strong>school</strong>s course, and the importance of trying them
out in the <strong>school</strong>s cannot be overemphasized.
One of the surest ways of obtaining the support of teachers in new programmes
is to involve them in the initial stages of apparatus development and trial. Physics
teachers are often willing to attend a course for apparatus construction, particularly
if their own <strong>school</strong> wil benefit from their labours, and some ministries
have had the foresight to set aside funds for this purpose. Such courses can be
valuable in the early stages of trials of a new programme, but it is unlikely that
they can provide a long-term solution to the apparatus problem of developing
countries. While significant quantities may be produced by judicious use of jigs
and power tools, mass production of apparatus is not an efficient use of a
teacher’s time or skills when he may already have been called upon to give up
much spare time to other activities connected with the project. But there is no
doubt that teachers enjoy such courses from time to time, not least for the opportunity
of interchange of ideas and discussion of teaching techniques over the
workbench.
185 Local Production of Apparatus in Developing Countries

13.6.1 Design re<strong>source</strong>s
Such a centre can usefully produce design re<strong>source</strong>s to enable teachers to make
their own apparatus. The Nuffield Physics Apparatus Construction Sheets are an
example. Such designs should take account of materials and facilities available
to teachers and of suitability for local climatic conditions. They should, therefore,
be produced locally by those responsible for curriculum development. In many
cases existing designs can be adapted or modified copies may be made from commercial
apparatus. Designs for teachers’ use wil naturally differ appreciably
from those used by manufacturers with their superior technical re<strong>source</strong>s.
If the centre is to give this kind of help, certain facilities are prerequisite. Professional
staff must include someone familiar with <strong>school</strong> courses, facilities and
technical personnel must be adaptable : experienced handicraft teachers may
be eminently suitable whereas many craftsmen and university-level laboratory
technicians can be too specialized. A well-equipped and well-stocked workshop
is essential. Typing services and facilities for reproduction of designs in quantity,
by stencil duplication (including electronic stencil-cutting from drawings) or by
photo-offset printing, must also be available.
A good design for teachers wil satisfy the following criteria. (a) It must not be
too technical in presentation; <strong>physics</strong> teachers are not usually trained to read
conventional engineering drawings. (b) Relatively sophisticated processes, such
as lathe-work, threading and tapping, accurate fitting, hard-soldering or welding,
grooving or routing and dovetail jointing, should be excluded. (c) Materials
should be carefully specified; it should not be assumed that teachers are familiar
with standard sizes of woodscrew, machine screw threads, and so on. Names
should be those in local use; for example, ‘ Masonite’ would not be recognized as
‘ oil-tempered hardboard’ or ‘waterproof hardboard’ in some places. (d) It
should be made quite clear where materials and sizes are critical and where substitutes
are acceptable. Possible substitutes should be noted; for example, galvanized-iron
roofing bolts for brass machine screws and hardboard for paxolin.
(e) Local <strong>source</strong>s of supply (or overseas where necessary) for material and components
should be indicated, together with current prices. It should be remembered
that conditions in capital cities are not typical of a country as a whole and
suppliers should be quoted for materials which may be readily available in the
capital but unobtainable elsewhere. (0 Notes should be given on all but the simplest
technical processes and on suitable tools. (9)Reference should be made to
relevant course publications or brief notes should be appended on the use of the
apparatus.
13.6.2 Support for teachers producing apparatus in developing countries
It has already been noted that the construction of apparatus can be a heavy
burden on the <strong>physics</strong> teacher and he wil need help in several ways.
Supply of materials. Obtaining all the items needed for a particular job may be a
fairly onerous task, especially when all purchases must be by official order and
186 Physics Apparatus

several suppliers are involved. It may also be impossible for a teacher to buy the
quantity needed; it is wasteful to buy 100 or 144 screws when perhaps ten are
needed, or a whole sheet of aluminium for the sake of using a small piece. There
is a strong case for the provision of certain materials through a curriculum unit,
especially scarce or imported items needed for apparatus for a new course. Some
degree of prefabrication may be justified where work can be simplified by the use
of power tools or jigs. This may impose quite a load on the technical and administrative
re<strong>source</strong>s of the institution concerned, but bulk buying and import,
together with reduced wastage and working time, could result in an overall
saving on a national scale even after adequate staff provision has been made.
Pliysiculassistunce. It is possible to harness the energies of pupils for the construction
of apparatus, but the ease and success of this operation wil depend on local
circumstances. Firstly, the overall <strong>school</strong> curriculum wil determine whether time
and space, including space for storage of unfinished work, wil be available.
Where woodwork and metalwork are taught, cooperation with the craft teachers
may be profitable, though designs may have to be modified to suit the requirements
of both craft-training and the <strong>physics</strong> laboratory. Secondly, it is necessary,
though not always easy, to foster enthusiasm for the project; making membership
of an ‘apparatus group’ a privilege may help, as may scheduling this activity
as an alternative to maintenance tasks such as sweeping or grass-cutting. Thirdly,
it will not be possible to maintain interest unless adequate provision of tools can
be made; pupils wil soon become bored by long periods of waiting to use a particular
tool. Lastly, the limitations of the scheme must be appreciated; unless the
re<strong>source</strong>s of a craft department are used much time wil be spent in teaching basic
skills and a high standard of workmanship cannot be expected, nor can designs
requiring fine technique be used.
Outside help may be available from <strong>school</strong> maintenance staff, commercial
carpenters, garages or light engineering concerns, sometimes free or at reasonable
charges. Use of these re<strong>source</strong>s may be limited to preparation of parts, timber
cut and finished to size, small metal parts and so on, or may involve complete
jobs. Samples may be essential, as local craftsmen are often unable to read a
drawing, however good it may be.
Without substantial assistance, teachers can seldom undertake the construction
of class sets and may have to confine their efforts to demonstration pieces.
Training. Many <strong>physics</strong> teachers who are willing to construct some of their own
apparatus feel that they have insufficient experience and knowledge of the techniques
involved. It is not easy to obtain guidance from <strong>books</strong>; those dealing with
woodwork and metalwork are usually concerned with the development of a high
degree of technical skill while those on laboratory technique generally consider
only more sophisticated methods. Few <strong>books</strong> deal with the range of fairly simple
techniques necessary for the <strong>physics</strong> teacher.
Instruction in simple workshop practice should, therefore, form part of both
pre-service and in-service courses for <strong>physics</strong> teachers, and workshop facilities
187 Local Production of Apparatus in Developing Countries

should be made available at institutions providing such courses. It is convenient
to combine workshop instruction with refresher courses and orientation courses
associated with the introduction of new programmes. Formal workshop exercises
are unsuitable and training should take the form of constructing several
pieces of apparatus with assistance from competent staff. Jobs should be selected
both to produce something useful for the <strong>school</strong> course and to offer practice in
operations such as preparation of wood to size, joining with screws, nails and
adhesives (including modern adhesives such as epoxy resins), cutting, bending
and drilling metals, riveting and soldering, electrical wiring and simple glassworking.
Repetitive work should be avoided as far as possible; planing one or
two pieces of wood to size is a useful exercise but most wood should be presented
ready to use. Simple jigs should be used to facilitate assembly in some cases.
An indirect benefit gained from courses of this type is that heads of <strong>school</strong>s are
likely to be more sympathetic towards requests for tools for the laboratory workshop
when they have seen examples of what can be made by their <strong>physics</strong> staff.
At least one institution (National Teachers’ College, Kyambogo, Uganda)
combines all these several means of assisting teachers by providing materials
(partly prepared), mechanical workshop facilities and jigs, and training, for
<strong>physics</strong> teachers to construct class sets of apparatus during short residential inservice
courses.
13.7 Large-scale production
When a particular design has been suggested, tried, developed, re-tried and
proved satisfactory, the next problem wil be that of providing sufficient quantities
of the final product for the <strong>school</strong>s where it wil be used.
Production in <strong>school</strong>s, supported by detailed drawings and possibly the supply
of materials, as described above, offers, at first sight, attractive economies, but it
must be accepted that there are limits to what can be done. Physics teachers are
scarce and often have, in consequence, heavy teaching loads. The time which
they can spend on apparatus construction is thus limited and if this work interferes
with other duties the real cost of the product wil be very high indeed.
Trained and technically competent laboratory assistants are rare in <strong>school</strong>s and
in many cases the teacher wil not have access to a workshop, but only restricted
space in his preparation room.
There is of course the assumption here that teachers wil be enthusiastic to produce
the necessary apparatus. There wil always be the enthusiasts, but if production
of apparatus were to depend on them, the <strong>school</strong>s with the enthusiasts would
get even better and the others would continue without the apparatus, unless it
was available from some other <strong>source</strong>. There wil also be some teachers who may
be willing, but who do not have the ability to produce the apparatus well enough
and the programme wil in consequence suffer. A mechanism for large-scale production
is therefore essential for a programme to be successful. Furthermore, the
local manufacture of <strong>school</strong> science apparatus on a large scale should be the aim
of every developing country, for the quantity of imports of manufactured articles
188 Physics Apparatus

would be reduced and there might even be the possibility of export to neighbouring
territories, both of which would help the exchequer. Local production would
reduce the costs to the <strong>school</strong>s and the interminable time lags between orders and
deliveries would be reduced too.
However, shoddy equipment which falls to pieces and does not do what is intended
of it wil do more harm to the scientific education of the pupils than no
equipment at all. so it is important that a careful check should be kept on the
quality of the production.
Before any large-scale manufacture can be attempted, a reasonable market
must be guaranteed and this wil need careful planning.
The following are some of the policy decisions that wil have to be considered :
(a) Is production to be undertaken completely by a single government factory?
If so, since this wil discourage the establishment of small factories under private
enterprise, will this curtail initiative? How wil government workers be encouraged
to work efficiently if costs are to be kept to a minimum? What training
programmes wil be required for technicians ?
(b) Is production to be undertaken completely by private enterprise? If so, how
wil quality control be established ? How wil excessive profits be curtailed? How
wil financial ‘ handbacks’, prevalent in some countries, be eliminated? Does
private enterprise have the existing skills to undertake production ?
Each country will have to solve the problems peculiar to itself. In the next section
a possible solution is outlined, not as a blueprint but as the starting point for
discussion.
13.7.1 Apossible scheme
A government agency might consider the establishment of a ‘cottage industry ’
production unit. This would consist essentially of a warehouse and a series of
workshops, all adjacent to one another. The workshops might be involved respectively
in glass blowing, optical work, metalwork, woodwork, electrical work and
plastics, with perhaps two or three small shops in each field.
Individual workshops could be rented to private manufacturers at low cost as
part of an overall agreement, renewable on a regular basis. The agreement would
specify the items to be produced and the selling cost of each item. The warehouse
would guarantee to purchase all specified items produced by the manufacturers
under the agreement. A further agreement would be required with the relevant
education authority, whereby a number of <strong>school</strong>s would be required to purchase
specified equipment from the warehouse.
The major difficulty in such a scheme would probably be in the drawing up of
initial contracts and subdividing the work between workshops. However, it
would have several distinct advantages:
(a) Such workshops rented at favourable rates should encourage private manufacturers
into the field of science equipment.
189 Large-scale Production

(b) Techniques already in existence amongst local manufacturers could be utilized
in the first instance, thus eliminating the need for extensive technical
training programmes.
(c) The warehouse would encourage manufacturers by the guarantee of a market
for materials produced.
(d) Costs would be reduced by the elimination of middlemen and by pre-arranged
contracts. In addition the system of ‘handbacks’ should be eliminated by the
warehouse selling direct to <strong>school</strong>s.
(e) Production would be limited and complex organization should not be required.
(f) Quality control could be established in the warehouse, where apparatus
would be checked prior to packing.
(8)New production techniques could be introduced gradually to manufacturers,
who might be encouraged to purchase new machines on a cooperative basis.
(h) The unit would serve as a pilot scheme on which future units could be patterned
in the light of actual experience.
I
(i) Future units could be established according to needs. These might be in the
same area, or in centres distributed strategically around the country. The rate at
which units could be established would depend on finances and market requirements.
13.8 International cooperation
Each country must ultimately determine its own apparatus and curriculum
requirements, but it would be a pity with the extensive amount of work to be
done if efforts duplicated each other too much. There are obvious advantages in
regional cooperation as practised in the countries of East Africa or in South East
Asia.
One possibility is the establishment of international regional centres which
could act as re<strong>source</strong> centres for various developing countries. Each centre
would house material from major educational programmes, and offer courses on
the materials. In addition it could collect information from developing countries
and disseminate it through the publication of suitable literature. It could undertake
the development of a wide variety of materials and apparatus, in excess of
any one country’s needs, but would guarantee that a country developing a new
programme had re<strong>source</strong> to relevant materials. Countries would still need to put
their own programmes together, but at least a great deal of duplication involved
in original research and development would be avoided.
190 Physics Apparatus

14 Physics Laboratories
It is generally agreed that <strong>physics</strong> laboratories are essential for the teaching of <strong>physics</strong> at
the secondary level, but the layout and furnishings of a <strong>physics</strong> laboratory can have a
profound effect on the kind of teaching that takes place in it. This is considered in the
introductory part of this chapter, which is based on a paper prepared by J. Beynon of
Unesco. The second part of this chapter is concerned with details of laboratory layout,
storage, furnishings and services. It is based on contributions from men experienced in
the field and who have taught in developing countries: R. F. Melton, G. C. Norman,
P. A. Whittle and M. K. Woolman. Reference is also made to the work of the Asian
Regional Institute for School Building Research sponsored by Unesco in Colombo,
Ceylon.
14.1 Introduction
The impression one gets from looking at most science laboratories is that they
have been designed to serve a never-changing function. Water supply and waste
pipes, electrical and gas lines are permanently cast into concrete floors, work
tables are built into the walls or around utility connections which erupt from
rather arbitrarily determined places in the middle of the room. Table legs are seldom
made of anything less dense than solid oak and support heavy bench, even
stone, tops. The teacher’s demonstration desk is comparable to the captain’s
bridge on a ship, from where he may stand and survey rows of pupils whose eyes
are lifted to him and to the blackboard and charts behind him, searching for the
information most likely to be demanded in the next exam.
One might ask which of the two has most influence on the way in which science
is taught in a space such as this: the teacher or the elaborate and impressively permanent
facility? Let us look at two typical laboratory layouts, Figure 8, and ask
how a teacher could be expected to teach or students to learn in such laboratories.
The basic idea behind such drawings is clear. The teacher is the <strong>source</strong> of
knowledge, while the students, all of whom are considered as equals, are expected
to integrate information from the teacher with the results of experiments,
dutifully done in unison in the mysterious alchemy of science education. Briefly
the options open to the students are:
(a) Look at the blackboard.
(b) Listen to the teacher.
191 Introduction

000000
000000
00000
Figure 8

(c) Try out an experiment.
(d) Compare his results with those obtained by his neighbours.
While this may or may not be a stimulating educational experience (depending
upon the quality of the teacher or the sex of the pupil's neighbours!), we should
not hold the teachers entirely to blame for the lack of imagination in the approach.
The laboratories of the type shown above effectively prevent him from
doing much else.
The fallacy in the planning of most existing laboratories was the assumption
not only that teaching methods were static but that science itself would undergo
little evolution. On the contrary, the last ten years have brought about farreaching
reforms of both the content of science education and of teaching
methods. These changes in their turn have often rendered the traditional laboratory
a museum piece.
It would seem appropriate therefore to look at a few of the changes that have
taken place over the last few years and then consider some specific new sciencelaboratory
designs that have been prepared to meet these changes.
14.1.1 Discouery experiments
What kind of environment is most conducive to inquiry and discovery? To
begin with, the pupil (or the pupil group) needs to have a place where apparatus
can be set up and left until such time as the discovery is made. (One cannot
schedule discovery into forty-minute periods.) Secondly, the pupil needs consultation,
sometimes with members of the group, sometimes with a pupil from another
group, sometimes with the teacher. This means that no pupil should be left
isolated on an island or peninsular bench with three pupils between him and
access to circulation space in the room. The same problem arises when the pupil
suddenly realizes that he needs additional equipment to help him in his work.
Thus functionally speaking, the environment for discovery requires that each
pupil have (a) access to the teacher and to additional equipment, (b) the possibility
to work either individually or with a small group of other students and
(c) a place to store his work, either in a small adjacent room or in an appropriate
place in the laboratory.
In practice this means flexible furniture arrangements including tables around
which up to four or five pupils can work and wall benches where individuals can
pursue their discoveries. It means that there must be a convenient circulation
space. It means providing extra space in the teacher's preparation room, or in
storage cabinets in the laboratory, where apparatus for longer-term projects can
be stored for the pupils.
An example of such flexibility is shown by the following different furniture
arrangements suggested by the Asian Regional Institute for School Building
Research sponsored by Unesco in Colombo. Figure 9 suggests a general layout of
the laboratory intended to provide working space for a class of forty. Figure 10
shows how the furniture can be moved as the subject matter changes (ARISB R.
1968).
193 Introduction

L 3 . 0 m L 1 2 . 0 m - I - 4 . 0 m ’ I
Figure 9
The first arrangement in Figure 10 is intended for general experiments not
requiring power, water or gas and the movable work tables are arranged in the
body of the room, away from the wall benches and thereby allowing plenty of circulation
space. In the second the pupils’ chairs or stools are collected from the
movable tables and arranged formally or informally near the teacher’s demonstration
bench. The third arrangement, for ripple-tank work, allows the ripple
tanks to rest on the floor, a vibration-free surface, and permits circulation space
for the teacher. The fourth arrangement is suggested for those experiments where
a.c. power is necessary. The power outlets are conveniently put on the wall
benches and the movable work tables are arranged along the wall benches to
avoid wires trailing across the floor. Similar principles can be applied just as
effectively for twenty-place laboratories instead of the forty-place one shown
above. They are discussed in detail in the Asian Regional Institute’s report.
14.1.2 Group projects
Science teachers are finding that many projects can best be done in small groups.
This makes it easier for the teacher to provide consultations with the pupils.
(During a one hour period he can give ten minutes attention to each of six
groups, but only two minutes to each of thirty individuals.) In addition, pupils
tend to teach each other when given collective responsibility to carry out a set of
experiments. A possible arrangement of a laboratory for such group work is
shown in Figure 11. Once again all the services would be provided in the wall
benches, though an additional asset in a <strong>physics</strong> laboratory of this nature might
be a ring-main set in the floor, providing electrical power sockets set in the floor
for use in the central part of the laboratory.
194 Physics Laboratories

-
arranged for ripple-tank work
Figure 10 Four different arrangements of furniture
1 6
arranged for use of a.c. power

standing
experiment
standing experiments U
on drawer
and cupboard units
n
14.1.3
1
Figure 11 Laboratory with furniture arranged for larger group experiments
Individual project space
There is an increasing tendency for pupils to undertake individual projects,
on their own or in pairs. Individual work of this kind is undertaken by pupils who
identify their own interests and, with guidance from the teacher, chart out their
own research projects. The result is that an experiment may well last over a period
of time, several days or even weeks. Clearly ‘typical’ laboratory spaces wil be
196
Physics Laboratories

Figure 12 Carrels for project work
inadequate for this and special facilities need to be provided. They should be
located near an equipment store-room since the pupil may frequently require
special items not normally kept in the laboratory.
Figure 12 is taken from a report by the Board of Education, Martinsville,
Virginia, USA, for a science unit for a high <strong>school</strong> which incorporates ‘science
carrels’ for individual project work.
U
14.1.4 Multi-discipline activities
There is also a move these days towards multi-discipline activities. The laboratory
designer should bear this in mind if the laboratory spaces which he designs
are to remain effective for the fifty to a hundred years that they may be in use.
It is most important that laboratories should be easily convertible for use by
other disciplines. Thus specialized facilities should be provided in the furniture
and equipment, not in the building itself. Ideally the laboratory space should be
convertible into any type of laboratory or even into classrooms and offices.
Furthermore laboratory services should also be generalized and clustered. Highly
specialized equipment may be required by each discipline.
An example of design that takes these parameters into account also comes
from Martinsville, Virginia, U S A, and is reproduced in Figure 13.
14.1.5 Workshop facilities
Teachers, just as much as pupils, are being encouraged to undertake creative
individual work. A good many of the curriculum-reform projects have put great
197 Introduction

emphasis on the need for them to develop apparatus which can be easily prepared
from materials readily at hand. This makes necessary the provision of a
14.1.6 Provision for the future
Having briefly considered how changes in science teaching can change laboratory
design, it should now be asked what the designer should do for countries where
science is still taught in largely traditional ways. Should he provide an outdated
laboratory to suit an outdated curriculum? The earlier proposition was that outmoded
laboratories may be perpetuating outmoded teaching methods. At this
point we would wish to go one step further by suggesting that laboratories should
always be designed so that the most avant-garde educational ideas could be
carried out within them. In practice it seems easy enough for a teacher to get
standard use out of a radically designed laboratory, while testing a radical curriculum
in a traditional laboratory is often difficult if not impossible. Perhaps an
198 Physics Laboratories

advanced laboratory design could even encourage the use of more modern teaching
techniques.
In any event it is hoped that those with responsibility for science education are
now questioning severely the appropriateness of the laboratories illustrated in
the beginning of the chapter and that in future they wil demand from their architects
better designs to suit modern science teaching.
14.1 .I Deueloping countries as initiators of change
Strangely enough, it is the least-developed countries that offer the greatest potential
for initiating widespread reforms in new science laboratories. The countries
with the least amount of accumulated capital investment in educational buildings
can plan now to build a whole educational system based on advanced ideas.
Another advantage of the developing countries is the well-defined nature of their
problems. Science curricula are being prepared that are uniquely suited to these
countries and which in turn have strong implications for laboratory design as a
whole. In addition, the lack of re<strong>source</strong>s often dictates that ingenuity should provide
the things which there is no money to buy. Developments in Ceylon, for
example, have led to laboratories not only better than the traditional laboratory
from a pedagogical point of view but also more economical.
The more developed countries too often tend to solve difficult problems by
paying a high price for elaborate equipment in specialized laboratories, whereas
the developing countries have shown that much <strong>school</strong> scientific work can be
carried out with home-made equipment produced from tin cans, boxes, bamboo
and elementary electrical equipment. Any success in this field is much appreciated
the world around. The extent to which developing countries can produce simple
laboratories with a minimum investment wil also be gratefully noticed and
applied by other countries.
14.1.8 Conclusion
In the rest of this chapter we consider various details associated with <strong>physics</strong>
laboratories.
The specific design ideas discussed in this introduction may or may not be
wholly appropriate to present-day science teaching in any given country, but
there is one cardinal idea that we should like to register: that science-teaching
content and methods are constantly changing and wil certainly change radically
several times over in the life of any science building. The designer's role is to ensure
that his work does not stand in the way of these inevitable changes. Basically
this means that only the floor, the structure and roof of the science laboratory are
liable to have any lasting value; the walls, services and furniture must all be planned
as things that can be discarded and replaced. when they have outlived their
usefulness.
199 introduction

14.2 Laboratories in developing countries
Of the need for laboratory space there is no doubt. If pupils are to acquire an
understanding of <strong>physics</strong>, the course in a secondary <strong>school</strong> must be based on an
extensive, direct experience of physical phenomena. For this laboratories are
essential ; <strong>physics</strong> lessons with any given class must include some experimental
work.
Unfortunately it is not unusual in some developing countries for laboratory
work in secondary <strong>school</strong>s to be regarded as a luxury and not essential for junior
forms, the laboratory being reserved for classes near to public examinations.
Where this is the case, there is often only a small proportion of pupils who opt to
continue with <strong>physics</strong> after their first two or three years of general science. It
seems not unlikely that the two situations are directly connected and the importance
of experimental work, with even the simplest facilities, in the early stages of
the secondary course, cannot be overemphasized.
Laboratories inevitably involve expense; the fittings, furniture and apparatus
for use in them are also expensive, essential and in some ways even more important
than the building itself.It is unfortunate that in some countries budgeting
for these items is considered separately, and this can result in a small wellfinished
laboratory with no equipment in it. The problems are complex, but in the
pages that follow are found some statements of principle and some practical
details which it is hoped may assist those trying to solve these problems.
14.3 The siting of laboratories
In planning the siting of buildings for a <strong>school</strong> it is most important to envisage
the potential needs of the largest <strong>school</strong> unit likely to develop, and to prepare a
long-term site plan that could accommodate such a unit. This can then be linked
to a phased building plan, with immediate needs being met by constructing the
buildings required as the first phase of the programme. In a developing country it
is a common experience for sudden pressures to arise for a <strong>school</strong> to expand
rapidly. Foresight ensures that when expansion is called for the result can be an
integrated and efficient block of laboratories, as distinct from the scattered
laboratories liable to result from piecemeal planning.
There are some fairly obvious advantages of having all the laboratories close
together: staff have to move less and find it easier to consult each other; availability
of laboratory staff is increased; movement of equipment between laboratories
is facilitated; and the cost of installing water, gas and drainage is reduced.
In developing a <strong>physics</strong> laboratory it is important to consider science requirements
as a whole. Location of <strong>physics</strong>, chemistry and biology laboratories near
each other not only ensures the optimum use of mutual facilities (such as the
workshop) and apparatus common to the disciplines but also encourages cooperation
between individual disciplines. In the initial stages a laboratory may be
used for more than one science and it is therefore essential to design it in such a
way that it can easily be adapted as later expansion takes place. Likewise it
200 Physics Laboratories

should not be overlooked in the planning stage that a laboratory designed in a
developing country for 16-20 pupils may at quite short notice be needed for twice
this number. Despite the obvious undesirability of classes of 40-50 pupils,
developing countries wil inevitably need large classes and floor space must be
allowed in new laboratories; if not, practical work may be abandoned.
In countries near the equator there are advantages if the longer side of a laboratory
or row of adjacent rooms runs east-west. This reduces the extent to which
strong sunlight enters the windows on either side. If there are windows facing
east or west, an outside verandah or corridor can be used to avoid strong sunlight
and the consequent heat and discomfort in the morning or evening.*
14.4 The structure of laboratories
Local conditions vary so much from country to country, or even within a country,
that it is impossible in this chapter to generalize about structure, and only a
few comments can be made.
Where the land is not unduly expensive or restricted in area for building purposes.
single-storey buildings have the advantage of simplicity in design and can
be constructed by small, local contractors without the need for special expertise.
The design can take account of what structural materials are available locally
and their relative cost. For instance, in the tropics local hardwoods are probably
cheaper and easier to obtain for roof trusses and purlins than fabricated steel. As
for roofing material, tiles are heavy and require strong trusses; galvanized corrugated
iron may be cheap but needs maintenance and can make rooms very hot
if there is no ceiling; aluminium costs more but does not corrode, it must be
thick enough to withstand high winds, being a softer metal; corrugated asbestos
sheets must be laid with special care to avoid stresses and are difficult to maintain
if cracking occurs as one cannot climb over them.
Conditions of temperature, humidity, dust, prevailing winds, precipitation
and lighting vary considerably from country to country, and each country is the
best judge of its own specific problems. In tropical countries, for example, the
problem of humidity and temperature necessitates particular attention being
given to cross-ventilation to ensure personal comfort for the pupils. This means
that the provision of blackout facilities for optical experiments and ripple-tank
work gives rise to problems; these are considered in more detail below.
* As regards orientation for comfort, two factors must be considered: the sun, which contributes to
discomfort, and the prevailing wind. which helps to cool building occupants. To accommodate the sun,
laboratories should be planned so that their window walls face to the North or to the South, or both if
there are windows on two walls. On the other hand, buildings should also he sited at right angles to the
prevailing breeze - particularly that which blows at mid-day during the most uncomfortable months.
In cases where the breezes are East-West in direction it is best to arrive at a compromise orientation.
and to increase overhangs for sun protection while attempting to redirect the breeze through strategically
placed shrubs and trees. Laboratories with windows facing East or West are almost bound to be uncomfortably
warm, and in addition the class wil be bothered by the excessive light resulting from the direct
rays of the sun. Exterior vertical panels can be installed to shade East- or West-facing facades, but at
considerable expense.
201 The Structure of Laboratories

It is hoped that enough has already been said in this chapter to stress the importance
of simplicity and versatility in the structure and design of <strong>physics</strong>
laboratories.
14.5 Size, shape and function of laboratories
The optimum size of a laboratory obviously depends on the number of pupils to
be accommodated. It is important to stress that in following an ‘inquiry approach’
to teaching the teacher is normally much in demand as a consultant and,
if the system is to work efficiently, class numbers must be kept to a minimum. It is
realized that large classes are not uncommon in developing countries, but it
is strongly recommended that every effort should be made to limit laboratory
classes to approximately thirty-two pupils, looking on numbers in excess of this
as a temporary state of affairs. If the pressure requires a class of over forty pupils,
it is almost certainly wiser to divide the class: one lesson under satisfactory conditions
is probably worth more than two under intolerable conditions of congestion.
Such a breakdown to smaller units has the additional obvious advantage of
enabling apparatus to go further: providing apparatus for over forty is a very
different proposition from providing it for twenty-five.
While it may not be realistic to ask for an average area per pupil of 3 m2
(30 ft’), practical work in <strong>physics</strong> does require 2.5 m2 (25 ft2) as an absolute
minimum. Most laboratories must therefore be 80 m2 to 100 m2 in area to accommodatTa
full class.
In laboratories for use by the fifth and sixth years of the secondary course,
more space is needed per pupil, but classes must of necessity be smaller. A typical
advanced-level <strong>physics</strong> laboratory would thus be about 90 m2 in area.
In the past, many laboratories have been built that are roughly 7.5 m wide by
12 m long. This shape has a number of disadvantages. When the room is furnished
with long narrow benches placed transversely, it is difficult for the teacher
to move round during the course of practical work and gain free access to any
pupil that he may wish to see. When he is teaching or demonstrating at one end, it
is difficult for pupils near the back to see the chalkboard or demonstration
because of the distance and the number of heads and shoulders in between. These
problems are reduced by using a shape that is more nearly square, typically
9 m by 10 m. The greater width does not introduce any great problem with singlestorey
buildings provided a light roof structure is used.*
It is important, however, that in every laboratory the teacher should be able to
arrange the whole class in comfort to discuss work done, to watch a demonstration
which all can see, or to follow work done by the teacher using the chalkboard,
a projector or other visual display. Some have been designed as two distinct
areas, one for practical work and the other for discussions with the teacher. While
* Whether or not it is possible to achieve this aim will depend on a number of factors: wide buildings are
easiest to build if one can use light-weight steel tresses and ifthe buildings are single story; local materials
may not be suitable for making spans in excess of the usual 7.5 m; artificial light may be necessary if the
laboratory has windows on one side only.
202 Physics Laboratories

this may in some circumstances be desirable, it does not in general make the most
efficient use of space available. The better arrangement, which it is noticeable
that both developing and more highly developed countries are now advocating, is
for a layout such that the pupils chairs or stools can be brought together in some
area of the room for discussion purposes. The Asian report advocates the following
for a teaching group of forty:
mz
10 group work-tables 43.8
40 chairs arranged for discussion
20 bays of fixed wall-bench
9.6
20.0
1 teacher’s demonstration table 7.8
1 chalkboard area 4.5
1 storage unit 2.3
Allow circulation space of 10 per cent 9.0
__
Total. say 97.0
-
This is a laboratory area of about 2.4 mz per pupil.
There can be no universal blueprint for the ideal laboratory. But it would seem
appropriate to conclude this section with a typical layout for thirty-two pupils,
working in pairs, with four pupils at each table, which has been advocated as an
economy laboratory for use in the Philippines. The laboratory arrangement is
very flexible, permitting regrouping of furniture according to the specific needs
of the class. It also allows the teacher to circulate freely amongst pupils at work.
(It was pointed out that it would not be difficult to seat forty-eight pupils in the
same laboratory by placing six at each table. particularly if the tables were
lengthened by thirty centimetres and the laboratory size increased accordingly.
However, a great deal is lost when pupils work in larger groups, say three to a
group, and this temptation should be resisted.)
14.6 Ancillary rooms
Certain ancillary rooms are essential for a <strong>physics</strong> laboratory; a preparation
room, a store-room and a workshop. It is not unreasonable that the space for
these should be 25 per cent of the space available for pupil use.
A preparation room should have a minimum space of 4 m x 4 m.* It needs all
services and a generous amount of storage space; also blackout and access, independent
of the laboratory, as well as a door into the laboratory. A common
preparation room may often be used between two adjacent laboratories, possibly
with a store or stores opening off it. It should be adequately illuminated, preferably
by daylight; ventilation is also important. It must be remembered that this
may be the room in which a laboratory assistant, if the <strong>school</strong> is fortunate enough
to have one, spends a large part of his working day.
* The ARISBR report recommends preparation-room space of 3 m x 4 m plus a darkroom, or
4 m x 4 m if a separate darkroom is not available.
203 Ancillary Rooms

3.1 5
12
A windows E experiment table electrical outlet
B table-top wall bench W workbench 0 stool
C cupboard
D demonstration table
SH open shelves
RT ripple tank
sink with tap
Figure 14 (a) Economy laboratory: layout for experiments.
(b) Economy laboratory: layout for discussions and demonstration
experiments
A workshop is another essential requirement for the <strong>physics</strong> teacher. This can
be part of the preparation room or it can be a separate room, which is certainly
preferable if it is shared with other science departments. A rigid working bench
fitted with a vice is necessary, with a set of hand-tools (preferably stored on a
shadow board on a wall) and a supply of materials. The door should be sited to
allow entry of large sheets and long lengths of material.
A darkroom is also valuable, particularly in <strong>school</strong>s with advanced-level
classes, but it is not essential. It need not be very large, but it should have a complete
blackout and all services. A matt black finish to walls, ceiling and floor may
204 Physics Laboratories

Figure 15 Economy laboratory: alternative layouts for ripple-tank work
be depressing, but is useful for physical optics. A labyrinth entry is helpful, and
one made of curtain material makes access easier for equipment, trollies and furniture.
If a teacher is to be able to improvise apparatus, he requires space (and
tools and materials) where he can do this in private, and the demands of the timetable
on laboratories wil mean that they are seldom available for such work.
With the decline in emphasis on accurate weighing, it seems unlikely that there
wil in future be a need for a separate balance room containing a row of chemical
balances.
The most essential ancillary room, however, is a store-room, which may or
may not be incorporated with the preparation room. It should be as large as possible
since the available space wil certainly be used as the years go by. It must be
filled with shelves and/or cupboards, as appropriate. So important is storage that
it is considered separately in the next section.
14.7
205
Storage of apparatus
The need for storage is almost always underestimated in planning <strong>school</strong>s. Sufficient
space is seldom provided even for traditional course apparatus, and the
present trend is towards large quantities of simple apparatus to enable pupils to
Storage of Apparatus

do their own experiments. This requires even more storage space. In addition to
normal equipment, space is needed for models and visual aids that the teacher
may construct or acquire, and also for mechanical and electrical ‘junk’ from
which pupils may learn a great deal about the working of technical devices.
Shelf space is often wasted by having shelves that are too deep or too far apart.
A spacing of fifteen centimetres between shelves is adequate for most items: tall
pieces of equipment can stand on top shelves. There is a great advantage in
having shelves which are adjustable in height to give flexibility of arrangement.
Storing apparatus on the shelves in uniform, clearly labelled cardboard boxes can
help to make maximum use of the space available.
Ordinary drawers are of limited use for the storage of <strong>physics</strong> equipment unless
fitted with compartments to stop things rolling or sliding when the drawer is
moved. It is, however, useful for the teacher to have a few drawers for his own
use, some of which can be locked.
Cupboards are helpful to preserve apparatus and to exclude dust and dirt. They
are also essential if humidity is to be controlled (see below). To avoid difficulty in
extracting things from the back, the depth of cupboards from front to back should
not be too great. Some cupboards should be just over a metre wide to accommodate
long pieces of equipment; others should be fitted with locks. Glass-fronted
cupboards at eye level are helpful as apparatus can be more readily located. It
will usually be found that hinged doors are better than sliding ones, but, if there is
limited space in front of a cupboard, sliding doors may be preferable. In the
tropics metal runners tend to corrode and simple wooden runners are better.
Simple wooden trays of standard size are very suitable for high-density storage
of small items of equipment. Trays which can be stacked on each other, or better
still can move on runners in a cupboard unit, can be particularly useful. Some
countries may have cheap plastic trays which can be used instead of wood.
The best use of space in a <strong>physics</strong> store is made by fitting wooden or angle-iron
racks some two metres high, with shelves having different spacing, those at eye
level being close together. A rack in the centre, with access from both sides, and
shelves round the walls give far more storage space than fixed surfaces at working
height.
14.7.1 Storage in tropical countries
Two extreme situations are likely to be encountered in tropical countries, sometimes
within the same country:
(a) very dry conditions for most of the year, with high or moderate temperatures,
in which the main hazard to apparatus wil be from dust,
(b) very humid conditions for most of the year, with high or moderate temperatures,
in which the main hazards wil be the rusting of ferrous metals and biodeterioration
affecting most materials.
Situation (a) is met by mainly closed storage in cupboards and drawers, the
latter offering better protection from dust than do trays on open shelves or racks.
206 Physics Laboratories

Good drawer units can usually be made from selected local timbers; imported
drawer units are not always satisfactory.
Situation (b) is more difficult. Air-conditioning is expensive in both capital and
running costs. It is not satisfactory if only the store is air-conditioned, because
there is condensation when apparatus is brought out. Air circulation is effective
in reducing bio-deterioration, forced air from fans being probably more effective
than the traditional cupboard heaters. Fitting a forty-watt bulb in a cupboard is
certainly better than nothing.
Storage on slatted shelves in fan-ventilated stores should be effective, provided
the trays for small components and apparatus have mesh or perforated bottoms.
The cost of trays should be regarded as capital expenditure. Store windows or
ventilation openings should be screened to exclude flying insects (even more important
if heater lamps are used), and furniture and fittings should be designed to
offer no refuge for cockroaches and similar vermin.
14.8 Services
Physics laboratories wil require services such as electricity, gas and water. Of
these the most important is undoubtedly the electrical supply: all three are discussed
below. Whatever is decided about the services to be provided, as far as
possible materials and fittings should be specified to conform to types in normal
use in the country concerned, so that replacement parts can be readily obtained.
Where <strong>school</strong>s enter large numbers of candidates for public practical examinations,
there is an advantage in providing every laboratory with all the essential
services needed for biology, chemistry and <strong>physics</strong>. While such provision also
makes for greater flexibility in the use of teaching space, the possible advantage
must be set against the higher cost. This question wil be influenced by the extent
to which public practical examinations are set in developing countries in the
future.
14.8.1 Electricity
As mains electricity is becoming generally available to <strong>school</strong>s in developing
countries, it is advisable to instal adequate wiring in anticipation of future developments.
It is cheaper to do this while building than to add it later. Further, it
is likely that an increasing number and variety of mains appliances and devices
will be used in the future, and so as many socket outlets as possible should be provided
in new laboratories. Three ring-mains in each room, each supplying five
double-socket outlets, is not likely to be excessive. Care must be taken to ensure a
good earth connection of low resistance, and no socket outlet should be fitted
within two metres of a sink. Sockets (switched) must be of the standard type in
national use.
A low-voltage unit supplying a large number of pairs of terminals on pupils’
benches, all connected in parallel, is not recommended. The system commits all
groups of pupils to use the same output at any given time, and any change in the
207 Services

current taken by one group of pupils affects the readings of all the other groups.
Further, the d.c. output of such units is normally unsmoothed, so that a correction
factor has to be applied to the readings of moving-coil meters. Such lowvoltage
supply units are also liable to be expensive, the cost of the wiring perhaps
exceeding twice the cost of the unit and the freight charges. It may be substantially
cheaper and more convenient to provide individual low-voltage transformers and
mains-operated d.c. supplies.
Simple circuit work can be carried out using torch cells, involving a low outlay
but a fairly high recurrent expense. Lead-acid accumulators may not get the
careful maintenance needed, especially in countries where there is a high turnover
in staff and an untrained laboratory assistant may not understand the need for
recharging. The life of such cells in <strong>school</strong>s in tropical countries may not be more
than two years. Nickel-Iron (NIFE) batteries are more expensive but are far
more suitable for <strong>school</strong> use (and misuse), and they are certainly better for
tropical conditions.
As it is now comparatively rare for a new secondary <strong>school</strong> in a developing
country to be without some form of electricity supply, it would appear that the
cheapest and definitely the most flexible arrangement is to provide individual
transformer/rectifier units.
14.8.2 Gas
It seems likely that in future less use wil be made of gas as a heat-<strong>source</strong> in <strong>physics</strong>
courses. It is normally adequate to provide about a dozen twin gas-taps, spaced
at intervals around the wall benches, with another twin-tap on the teacher’s table.
Demand for gas wil depend on the course, but it should always be provided.
Where piped ‘town gas’ is available there are no problems about its supply, but
in many developing countries it wil be necessary to use ‘bottled gas’. Fittings
and burners must be appropriate for the type of gas used.
If bottled gas is used, the cylinders should be outside the building in a properly
constructed cupboard or cage that is kept locked. A cupboard should have vent
holes near the bottom so that any escaping gas, which is heavier than air, cannot
accumulate inside. It is desirable to have two sets of cylinders with a changeover
valve, particularly for an installation supplying more than one laboratory.
Empty cylinders should be replaced as soon as possible with spare full ones.
It should be possible to turn off the supply to each laboratory by means of a
stopcock near the point at which the supply enters the room. Slight leaks may
develop in the piping. In the tropics gas-taps may leak if the grease on them dries
out. The system should be tested every six months by attaching a simple water
manometer to an open gas-tap with all the other gas-taps closed, and turning off
the stopcock from the supply. Leaks may be located by brushing the suspected
part with an old paint-brush dipped in strong detergent solution and watching
for bubbles to grow. Action should be taken at once.
A useful economy to save the cost of all plumbing is to design a special service
trolley. The one illustrated in Figure 16 is a Kyambogo design for such a trolley
with gas-cylinder and water.
208 Physics Laboratories

Dexion trolley
Figure 16
14.8.3 Water
Water supplies are not nearly so important in <strong>physics</strong> teaching as in chemistry.
Provision of four to six outlets should be ample, unless the laboratory is likely to
be used for chemistry as well as <strong>physics</strong>. A fairly high pressure is useful and roof
tanks should be avoided if a good mains pressure is available.
Swan-neck taps should be avoided as they are easily damaged and cannot
usually be replaced locally. Bib taps, on standards of ordinary galvanized waterpipe
or wall flanges, are better. A height of thirty centimetres above the bench is
adequate. Riffles must accept tubing from about 6-10 mm internal diameter : it is
unfortunately too common for nozzles with a minimum diameter of 12 mm to
be specified, which may be all right for garden hoses but are unsatisfactory for
<strong>school</strong> laboratories. Fine regulation of flow should be possible.
In some areas in developing countries the water supply is limited, or expensive,
and care must be taken to avoid waste. Some supply systems may not give a sufficient
pressure to operate filter pumps, which are in any case wasteful where the
supply must be conserved.
If the supply is unreliable, it may be advisable to instal roof tanks in each block
of laboratories to maintain a supply during temporary breakdowns. Such tanks
give only a very low pressure, in which case one needs to avoid using very smallbore
taps. Swan-neck taps are expensive and unnecessary. Tall apparatus may be
filled by attaching rubber tubing to more ordinary taps.
Provided one large sink is fitted in each laboratory. say 50 cm x 30 cm x
20 cm deep, the remaining sinks can be small to reduce the loss of useful bench
area. They can be made of a black plastic such as Vulcathene, and 40 cm x 15 cm
x 15 cm deep has been found to be a useful size. Four or five such sinks. set in the
wall benches at intervals, are adequate for all normal purposes, with two taps per
sink. It is very useful to have detachable covers to the small sinks as this provides
additional bench space during the periods when the sinks are not required. The
large sink should, if possible, be provided with hot and cold water.
209 Services

~~
Where very considerable economy is necessary, and where water is not readily
accessible, note may be taken of the Kyambogo service trolley, mentioned above,
which provides portable supplies of gas and water. Much can be achieved with
this in a <strong>physics</strong> laboratory now that running water is less frequently used in
<strong>physics</strong> teaching than was the case in the past.
14.9 Laboratory furniture
From what has been said already in this chapter it wil be apparent that flexibility
in laboratory layout is recommended. Pupil workbenches should be of sturdy
design with a good horizontal surFace. They should not be fixed to the floor either
deliberately or accidentally (by water or electrical conduits).
Each pupil needs a width of not less than seventy-five centimetres to give him
elbow room for practical work. Tables at which pupils work on one side only
need to be seventy-five centimetres wide; for pupils to work opposite each other
the minimum width is 1.4 m. The construction of movable tables should be sufficiently
rigid to give a firm working surface yet it is desirable that the tables should
be light enough to be carried by small groups of pupils when necessary.
The height of the bench surfaces depends on whether pupils normally stand or
sit when doing experiments. If they stand, a height of ninety centimetres is suitable;
if they sit, seventy-five centimetres may be more comfortable. Stools should
be provided of the appropriate height, so that for comfort the top of each stool is
thirty centimetres below the top of the working surface. One advantage of the
lower benches is that it is easier for pupils to see the lower part of the chalkboard
over the shoulders of their fellows in front. Such visibility has sometimes been
assisted by providing the teacher with a raised plinth. One effect of such a plinth,
however, is to restrict a considerable area of the room for the sole use of the
teacher as an elevated performer, and the idea is not recommended in the light of
modern teaching techniques. *
* The height of the bench surface not only depends on whether pupils normally stand or sit when doing
experiments, but also depends on the average height of the students. The height of a bench used for
students standing up should be 0.52 times the mean standing height of students of that age group. For
seated students the table height should he 041 times the mean standing height. Translated into usable
terms, this means 76 cm and 60 cm respectively for Asian children 14 years of age, while the figures for
North American children of the same age would be 85 cm and 67 cm. Stools should he provided so that
the top of each stool is 22-24 cm below the top of the working surface (see table below).
Multi- Asian North American
plying children children
factors 14 years 18 years 14 years 18 years
(dimensions in metres)
Mean standing height H 1.46 1.63 1.63 1.72
Stand-up working height 0.52H 0.76 0.85. 0.85 0.89
Sitting working height 0.41 H 0.60 0.67 0.67 0.71
Difference between working height and sitting height 0.15 H 0.22 0.24 0.24 0.26
210 Physics Laboratories

It can be very helpful to have an open shelf under the table for pupils’ <strong>books</strong>,
leaving the top surface completely free for apparatus. Drawers should not be
included in work tables. In practice they are not readily accessible, they tend to
be the repositories of debris and of course they add to the weight. It is essential
that the tops of the table should overhang the frame so that G-clamps may be
used to clamp equipment to them.
The wall-benches should carry all the services. They can either be supported by
heavy angle-iron grouted into the wall or be supported on cupboard units at
intervals. the remainder being left free from supporting legs to allow plenty of
knee-space. The width might be 50-60 cm. Not only wil the wall benches provide
the services for the pupils’ work tables, but they can also be used for experiments
which can be left set up for a period. It is essential that the fixed wall
benches should be at the same height as the movable workbenches. They too
must overhang the frame so that G-clamps can be used to clamp equipment to
them. The working space on the wall benches can be increased if flush-fitting
wooden sink covers are provided, as mentioned already.
In a developing country where a mains water supply is not available a water
container placed above the bench can provide water, while a bucket beneath the
sink can take it away. This, of course, is not as convenient as having tap water laid
on and should be considered only as an interim measure.
water container attached
to wall
I
sink cover with drip-hole
Figure 17
The teacher’s demonstration table can be almost the same as the pupils’ work
tables, though it is convenient to have services on it. It should be at the same
height as the pupils’ tables and any apparatus trolleys that may be in use. An
211 Laboratory Furniture

apparatus trolley alongside the table usefully extends the demonstration surface.
It is also relatively inexpensive to add end-flaps to the table which, when raised,
can give further space. It can be very useful to include a few drawers and cupboards
for extra storage space. There is general agreement these days that a
plinth for the teacher’s demonstration table is undesirable.
A chalkboard (blackboard) behind the demonstration table is essential and
should be as long as possible. The height is important: there is no point in the
bottom edge being at a lower level than can be seen by the pupils sitting furthest
away, or in the top edge being beyond the reach of a tall teacher. A board on a
hinged flap at either side gives the possibility of increasing the effective area. One
panel may be ruled with a grid for use in drawing graphs and another may conceal
a white screen for projection purposes. A good quality blackboard is a worthwhile
investment, though painted plywood or blockboard is cheaper.
A display board somewhere in the laboratory is a desirable asset. Many <strong>school</strong>s
find it helpful to set a space aside to display <strong>books</strong> and periodicals, to act as a
class reference library. Background readers are a feature of many projects and it
is helpful if these can be displayed in the laboratory.
14.10 Lighting, Ventilation and blackout
These can be serious problems in developing countries especially in the tropics.
Laboratories there require plenty of daylight, especially in those areas where
electricity is not available during the day. There must however be means for controlling
the light level for optics, visual aids, etc. Control of ventilation is also
important: there should be plenty of through draught, necessary most of the
time, but it should also be possible at times to eliminate draughts completely. It is
rare for these conflicting requirements to be fully satisfied in existing <strong>school</strong>
laboratories in tropical climates.
Some simple form of blackout is virtually essential in all <strong>physics</strong> laboratories.
Simple rectangles of heavy black drill material, slightly larger than the window
openings, can be sewn to form blinds. A wide hem with open ends both top and
bottom permits a broomstick to be passed through each. Each blind is supported
by resting the ends of the upper broomstick or rod on two woodscrews, or large
cuphooks, plugged in the wall just above the top of each window. When not in use
the blind can be rolled round the lower rod and tied with string or tape. In the
tropics this has an advantage over curtains in that the blackout may be transferred
readily to any other room with similar windows, provided the necessary
screws are fitted above the windows. It can, for instance, be used to screen the
windows of a preparation room to hide the apparatus being assembled for a
practical examination! Ordinary curtains can be used, but they are expensive and
tend to tear with the strain of being drawn repeatedly.
212 Physics Laboratories

14.11 Laboratory organization
Where funds are limited, it is particularly important that equipment bought or
made shall be kept in service for as long as possible. In situations where there are
frequent changes of staff, stability of staff not being one of the strong points of
<strong>school</strong>s in developing countries, it is important to have a system by which a new
teacher can ascertain readily what apparatus is available and where it may be
found.
Storage should be planned in an orderly way so that each piece of equipment is
kept in a specific place. Each cupboard should bear a general label indicating the
type of apparatus it contains and a list giving details, including quantities.
Objects such as spring balances or pulleys can be kept hanging from cuphooks.
If the number of hooks matches the number of objects, it is possible to see at a
glance when one is missing. Lenses or glass blocks can be kept in slots, again
matched to the correct number. Arrangements such as these facilitate rapid
checking of multiple items. This is particularly necessary with small items like
lenses, magnets or plotting compasses which may gradually disappear if not
checked in every time after use.
Maintenance. The teacher should ensure that pupils report any defective or
damaged apparatus at once. Such equipment should be withdrawn from use and
repaired as soon as possible. Pupils show less respect for anything in poor condition
and further damage is likely to follow. Defective electrical equipment
should be withdrawn at once because of possible danger. The same applies to
cracked glassware.
In humid climates corrosion of steel objects may be a problem, and they should
be coated regularly with a thin smear of petroleum jelly.
Accumulators should be charged regularly, particularly lead-acid cells which
deteriorate rapidly if left standing. Arrangements should be made to maintain
them over long <strong>school</strong> holidays.
Ordering supplies. Where apparatus is imported from overseas, there may be
delays of a year or more between placing the order and receiving the goods.
During this time the teacher who placed the order may have left the <strong>school</strong> and
possibly the country. It is thus vital that proper records should be kept. by the
head of the <strong>physics</strong> department, of all orders placed and goods received, with
duplicate copies available in the main <strong>school</strong> office. When the person responsible
leaves, these records should be handed on to his successor.
Stock records. If a <strong>school</strong> has no official inventory system, the head of the <strong>physics</strong>
department should compile his own record of all equipment held. A card-index
system permits easy insertion of new acquisitions in alphabetical order. but care
must be taken to avoid losing cards. A proper check of all equipment held should
be carried out once a year.
213 Laboratory Organization

15 Audio-Visual <strong>Teaching</strong> Materials
This edited chapter is based on contributions from H. Ootuka, M-Y. Bernard, H. Messel,
Isais Raw and C. B. A. McCusker, together with a very detailed contribution from
A. V. Baez. The chapter attempts to survey the range of audio-visual aids which is now
available to those developing new programmes. Any country concerned with new
programmes wil need to decide which aids it will be using and it wil have to plan its
organization so that materials are available for use in that medium. A distinction wil be
made between hardware (cameras, projectors, receivers and so on) and software (slides,
films,film loops, transparencies, etc.): surprisingly enough it is often easier to obtain
adequate hardware than software. It is useless to provide television receivers in every
<strong>school</strong>, for example, if there are not enough programmes to make effective use of the
medium. Careful initial planning is therefore essential if valuable funds are not to be
wasted. The aim of this chapter, like the aim of education in general, is to motivate and
inform and it wil have served its purpose if it does a little of each.
15.1 Introduction
The aim of science education is not simply the transmission of data and modern
dogma. If this were the case, the fast development of new mass-communication
devices would solve the problem of science education: they can offer today information
through pounding massive continuous repetition and even more subliminal
inculcation. We expect instead to build, through science education, a new
attitude that prepares the young to think for themselves, to arrive at objective
conclusions from a set of observed data and to plan new experiments to check
their conclusions, and so to become able to face a fast-changing world. The building
of this attitude, learning the ‘tactics and strategy of science’ as Conant put it,
cannot be accomplished except by putting the pupils through the process of
doing it. Throughout this volume stress has been laid on pupils doing experiments
themselves.
Some educational authorities in the developing world imagine that experimental
work is not feasible, because of the cost of apparatus, and yet invest far
larger funds in educational television, including in many cases the receivers.
Television has its proper use, but there is no substitute for the actual performance
of an experiement. No one would accept a surgeon trained only with the most
modern visual aids !
214 Audio-Visual <strong>Teaching</strong> Materials

But. despite this warning there is no doubt at all that various forms of visual
and audible aid can be great assets to the teacher and can promote the effective
teaching of <strong>physics</strong>.
It has been said that audio-visual aids can ‘bring the world to the classroom’.
This means that they can bring some of the characteristics of real experience
within reach of the pupil. Audio-visual aids are no substitute for real experiences,
but they can motivate and inform, and in some cases can do so better than the
real experience. A visit to a hydroelectric plant, for example, may be more impressive
and motivational than seeing a film about it, but an understanding of the
workings of a dynamo can perhaps be achieved more readily with the help of a
well-designed film or film loop.
The saying ‘ Hear and forget, see and remember, do and understand’ makes a
strong case for practical or laboratory experience. But the content of science is
now so vast that we cannot expect pupils to have direct experience of everything.
They cannot do all the experiments. The next best thing is to bring the experience
to the pupil so vividly through sight and sound that he is put on the road to
understanding.
One of the recent trends in education is to demand that the educational planner
and the teacher specify behavioural objectives for curricula and syllabuses as well
as for teaching materials and aids. If it is clearly understood what we want the
pupil to accomplish, it is easier to choose audio-visual aids to serve the purpose
and to produce new ones.
Another trend has been to shift the emphasis from teaching to learning. This
has been spurred by the realization that there wil never be enough teachers at the
rate we are producing them. This has, in turn, given impetus to self-instructional
techniques in the form of programmed learning, the use of magnetic sound
recordings coupled with visual materials and computer-assisted instruction. In all
these systems as well as in the classical classroom lecture audio-visual devices
have become important aids to learning.
A narrow meaning of learning implies only remembering. A broader interpretation.
more in harmony with the world-wide demand for relevance, demands
understanding as well as recall. Audio-visual aids can be designed to assist in the
basic aims of education, which include both learning and understanding. Some
audio-visual aids do this best through information, others through motivation
and still others provide both.
15.1.1 Types of visual and audible aids
If this were a comprehensive survey of audio-visual aids, it should begin with the
chalkboard and the spirit duplicator, which remain among the least expensive
and most universally used visual aids. It might end with electronic video recording
and computer graphics, but these are highly expensive and are not likely to be
relevant to most countries when a better economic return can be obtained from
other aids, especially at secondary-<strong>school</strong> level.
21 5 Introduction

In this chapter detailed attention wil be given to (a) <strong>books</strong>, (b) slides and film
strips, (c) the overhead projector, (d) films,(e) film loops, (f) the adding of sound
to visual techniques. Finally, reference is made to television and radio, and the
chapter concludes with an account of television work done in Australia which
suggests possibilities for the future.
15.2 Books
Books must not be overlooked as very important visual aids. Any teaching of
<strong>physics</strong> will ultimately need well-prepared <strong>books</strong>, but there is frequently a lack of
proper understanding of the role of the book, what it should contain, how to
illustrate it and how to make it appealing. Cutting the cost of illustrations is
common, and at the same time the ones appearing may be useless. Some classical
photographs are common, such as a view of a refinery in chemistry <strong>books</strong> which
does not illustrate anything but metal tubes. This may go as far as a ‘dissectable’
reactor printed with transparent sheets, costing almost as much as the rest of the
book. Proper use of illustrations needs particular attention. There is plenty of
scope in <strong>physics</strong> <strong>books</strong> for using the latest techniques in providing illustrations :
time-lapse photography, stroboscopic photography, and reference to modern
phenomena (for example, bubble-chamber photographs when considering conservation
of momentum).
Where <strong>books</strong> are being written for new programmes they need to be very
closely integrated with the programmes. Reference <strong>books</strong> are desirable in the
final years of secondary education, not least to prepare pupils for the use of <strong>books</strong>
at the tertiary level when they wil probably cease to rely on any one text. That
they are encouraged to use several texts at the end of the secondary level is
deliberate policy in Harvard Project Physics and the Nuffield Advanced Physics
course for this specific reason. Most projects wil want a special pupils’ text for
the course, but again organizers wil need to think carefully what is the purpose
of the text. If the course is designed to foster the spirit of inquiry, there is little
point in providing a textbook which gives all the answers. Such a book could work
against the spirit of the teaching, suggesting ‘right’ answers and thereby encouraging
an authoritarian approach. There is an increasing awareness, at least
in some projects, that it is more helpful to provide a sequence of well-illustrated
background <strong>books</strong> rather than a standard textbook, especially in the earlier
years at the secondary level. This is not to say that text<strong>books</strong> are necessarily
wrong; merely a plea that new projects should look closely at the purpose of the
textbook.
Most text<strong>books</strong> incorporate questions. With the new projects these tend to
involve induction and deduction and cannot be answered simply by remembering
the text or substituting in formulae. Good questions should be an integral
part of the actual teaching. If, on the other hand, the textbook is merely the
medium for these questions, it may perhaps be wiser and more economical to
print the questions in a separate book. These are issues on which all new projects
will have to decide: there is no panacea.
21 6 Audio-visual <strong>Teaching</strong> Materials

15.3 Slides and film strips
Probably the least expensive of the very effective modern visual aids is the photographic
film transparency designed for projection. (Mounted in a rigid rectangular
mount it is usually called a slide or transparency. A series of related still
pictures on a roll of film is called a film strip. In what follows, if there is no
danger of confusion. we may use the word slide when. in fact, we mean slide or
film strip.)
For teaching purposes the transparencies, in either slide or strip form, should
be arranged in a logical sequence. The instructional use of the visual image is enhanced
by verbal material sometimes on the picture or in the form of titles. It can
also be recorded on magnetic tape (see later). Related printed material for the
teacher or the pupil - often written by the teacher himself - is also very useful.
The most widely used film-strip frame is the single frame of a standard 35 mm
film (24mm x 35mm). These slides and film strips have almost replaced the older,
larger slides. The size of the potential audience that may be reached by slides and
film strips can be judged by noting that the projected image seen in the normal
motion-picture theatre originates in a single frame of the same kind of 35 mm
film.
The film can be colour or black-and-white. There is a strong trend towards
colour because it is very effective in attracting the attention of the pupil and
because the higher cost of colour is not prohibitive in slides or film strips in which
the total amount of film used for one lesson is relatively small (twenty frames
require only about 50 cm of film).
The film strip is preferable (a) if it is important not to lose any individual picture,
(b) if the order of presentation must be kept intact and (c) if storage space is
to be kept to a minimum. Individual slides take up more space than a film strip,
but when stored in trays this preserves the order of presentation with the added
advantage that they can be edited easily.
15.3.1 The scope of transparent slides
Anything that can be photographed in colour or black-and-white can be projected
as a slide; anything you have ever seen in a book, magazine or film can be
converted into a slide. Charts and graphs. whose minute detail would take an
unwarranted amount of time to copy on a chalkboard make ideal subjects for
projection. Drawings, paintings and, of course, real objects can be photographed
for projection and stored for quick retrieval and re-use.
In the past, large wall charts were often used as graphic illustrations. Transparencies
can do the job better. They can fill a larger area and can be stored more
readily. The older type of projector which can illuminate the page of a book and
project it directly on the screen produces an image far less brilliant than that of a
slide, making it essential to darken the room very much more than is needed for
transparencies.
Another simple use for transparencies is to project a picture or a chart on a
large piece of cardboard or white paper. The pupil can then trace the outline of
217 Slides and Film Strips

the projected picture using a felt pen or a brush and in this way create his own
wall charts, a procedure which might be of particular interest in some countries.
15.3.2 Cost
The equipment is relatively low in cost. A 35 mm camera may cost between $25
and $250 in the United States, depending on the complexity of the optical and
mechanical components. Projectors in the United States cost between $30 and
$300. The cost is influenced by the power of the lamp and the sophistication of
the optical and cooling systems. If a single frame of 35 mm film is to fill a cinema
screen, a very brilliant light <strong>source</strong> and an expensive cooling system are needed.
The considerably lower power of the lamp used in the classroom projector (300
to 500 watts) limitsthe reflecting-screen size to about 1.5 m x 2 m when projected
in a semi-darkened room.
15.3.3 Rear projection
Some striking new developments in screen design permit projection without the
necessity of darkening the room, which often detracts from the pupil's ability to
take notes. Darkening the room is sometimes conducive to a passive attitude on
the part of the pupil, who may react to the darkness as he does in the movie
theatre which he probably associates with relaxation. By using rear projection,
however, through a translucent screen whose dimensions are approximately
24 cm x 35 cm (not much different from the size of a television screen) the image
is so bright that the room does not have to be darkened. Operating in a room with
normal illumination has obvious advantages in a learning situation.
15.3.4 The benejits ofproducing slides andjilrn strips
Space does not permit giving instructions on slide making, reference to which
can be found elsewhere, but it is worth stressing the value of teachers making their
own slide and film-strip presentations.
The teacher wil discover that he cannot make a slide presentation that teaches
effectively unless he has thoroughly understood the subject himself. Making
slides is, therefore, a profitable teacher-training activity, from which of course the
pupils will benefit if the presentation is vivid and precise. The cost of making
slides should not be prohibitive, even in developing countries, and it might open
the door to an educational industry with many ramifications.
15.3.5 Conclusion
The low cost and the relative ease of production of transparent slides (needing
collaboration between scientist, teacher and film technician) soon enables an
extensive library to be built up in <strong>school</strong>s. The slides and film strips can be particularly
effective if combined with suitable audio tapes or records and this question
of combining audio and video techniques is considered separately below.
218 Audio-visual <strong>Teaching</strong> Materials

15.4 The overhead projector
Although the principle of the overhead projector is as old as the science of optics,
and models of it were in use about twenty-five years ago, it is only recently that it
has become very popular and in certain functions competitive with the 35 mm
slide projector. Mass production, with a consequent drop in price, has been
made possible through certain technical advances. These include a very brilliant
and compact light <strong>source</strong> and the flat, plastic Fresnel lens which replaces the
heavy and expensive condenser lens of older projectors. The latest versions of the
instrument are so light that they can easily be carried in one hand from one room
to another, and some cost only $150. With this projector, light from the intense
<strong>source</strong> is focused by the Fresnel lens to pass vertically through a transparency
(20 cm x 25 cm), placed horizontally on a platform over the lens. The light continues
upward through a glass projection lens and is then reflected to emerge
horizontally over the head of the lecturer; hence the name overhead projector.
The final image is formed on a white, vertical (or slightly tilted) projection screen
or on a large white wall. The light is so intense that the classroom does not need to
be darkened.
The transparencies for the overhead projector range from plain plastic, on
which the teacher can write with a felt pen, to simple plastic graphics and professional
multicolour overlays. Two big advantages are that information can be
added to the transparency while the lecture is in progress, and that part can be
covered by a piece of paper to be removed later to reveal the continuation of a
logical development.
Transparencies are quick and easy to prepare, and felt pens with washable inks
and several colours may be used if desired. Information can also be printed
straight on to a sheet with a special thermal copier in a matter of seconds, giving a
black-and-white copy of a single page without any chance of an error in the
copying; it can be as detailed as a sheet of music or as complex as an etching.
There are also commercial means to mass produce prepared transparencies in
colour, and some science-teaching projects have incorporated these in the
materials they supply to <strong>school</strong>s.
The overhead projector can be thought of either as a ‘super’ slide projector or
as a new form of chalkboard. It differs from the chalkboard, however, in at least
two ways. Once the message is erased from the chalkboard there is no way of
checking what has actually been written during the classroom presentation. The
transparency, on the other hand, is a permanent record that can be viewed again
at will.The other difference is that erasing the chalkboard and filling it with information
takes time and produces chalk dust. Putting ten transparencies on the
projector in succession during the lesson is the equivalent of filling the blackboard
(and erasing it) ten times. Because transparencies can be prepared in
advance they can be virtually error free. You may lose the spontaneity of the
chalk-talk but you gain the advantage of error-free slides. It is possible of course
to write with washable ink on the ready-made slide during the lesson and erase it
at the end of the period without removing the permanent message that had been
imprinted on it by the photocopier.
219 The Overhead Projector

It is also possible to use overlays consisting of plastic sheets containing supplementary
information which shows through the transparent part of other overlays.
One sheet might show the external appearance of a cathode-ray tube, for
example. The next might show how the cathode is placed within the tube.
A third might illustrate the effect of the focusing anode on the electron beam, and
so on.
Still another possibility is to put actual miniature equipment on the projection
platform and demonstrate such things as magnetic fields, ripples on water, experiments
on the polarization of light in colour, surface-tension effects on the
surface of liquids, electric circuits and meter readings, the standing waves of cork
dust in a Kundt’s tube, a demonstration of wave versus phase velocity, etc.
The academic job of inventing new transparencies for teaching <strong>physics</strong> using
the overhead projector, and their actual production, is something that can readily
be undertaken even in a financially depressed developing country, with the benefits
to the teachers involved which have already been cited when discussing the
preparation of slides.
As with slides, there are considerable advantages in combining the use of the
overhead projector with audio tapes as discussed below.
15.5 Films
When asked what films might do for education a film producer once said : ‘I can
put on film anything you have ever seen or imagined.’ This sums up neatly the
great potential of films.Film is capable of producing a more realistic approximation
to experience than any other visual aid.
Space and time, in a sense, can be compressed or expanded. The camera can
look through a telescope at large and distant objects, or through a microscope at
incredibly small things. The film can endlessly multiply the number of observers
who can see what the camera objective saw: a complete audience can see what
would have to be viewed individually through a microscope or a telescope. The
camera can compress a lengthy experiment into a minute or two and speed up the
creep of a glacier or the blossoming of a flower. It can slow down a bullet in
flight or a cobra as it strikes.
It can travel to the moon and bring back a photographic record. It can witness
dangerous events such as natural and man-made explosions. It can go into a
high-temperature enclosure, inside a Dewar vessel full of liquid helium or to
places where radioactivity or pressure would be lethal. In medical research it can
take pictures of objects inside a human body.
It can show on the screen objects of low intrinsic brightness by using long exposures
and sensitive emulsion. It can also film using illuminating beams outside
the visible spectrum: X-rays, ultraviolet and infrared light. It can use electron
beams to make visible what is normally invisible. It permits us to see things that
are too large, too distant, too expensive, too evanescent, too fragile, too small,
too heavy, too dangerous or too time-consuming to bring into the classroom.
Films can motivate and inspire. They can stimulate inquiry and experiment.
They can also inform, teach, and promote learning, understanding and acquisi-
220 Audio-Visual <strong>Teaching</strong> Materials

tion of attitudes and skills on the part of both students and teachers. All of these
potentialities must be obvious to a parent who has seen his child glued to a television
set on which much of what he sees was first produced on film.But it is
easier to be convinced of the power of film than it is to make good teaching films.
15.5.1
Films in teaching
Films in teaching can serve many different purposes. Firstly they are powerful
tools in showing the relevance of what is studied in the classroom to what happens
outside; they can show that <strong>physics</strong> does not build up a world of its own
divorced from everyday life. Such films can be of great motivational value,
awakening an enthusiasm for <strong>physics</strong>, both for its own sake and for vocational
purposes.
Secondly they can be used as an integral part of the teaching. It has been
stressed elsewhere in this volume that the only way to come to an understanding
of <strong>physics</strong> is through pupils doing experiments for themselves. When the apparatus
is too elaborate or too costly, it may be necessary to substitute a demonstration
by the teacher; there is also the factor of time, which wil not allow pupils to
do all the experiments they could do. Sometimes a demonstration may not be
possible, again on the grounds of cost of apparatus or of time, and a film of the
experiment may be a very good substitute. It also has the advantage that everyone
in the audience can see the experiment clearly, even close-up detail, when the
right filming techniques have been used. Michel-Yves Bernard of France has put
a strong case for this in university teaching: how much more economic in time it
is, in the long run, to film an elaborate experiment which wil always work on
film,thus removing the risk of an experiment which does not work and leaves the
students with only a half-memory of what ‘ought to have taken place’. A programme
producing such films for university teaching is being actively pursued in
France at the Centre Audio-Visuel, Ecole Normale Supkrieure de St Cloud.
A teaching film is ideal when the experiment is too elaborate for setting up in
the classroom at all,for example in showing something as basic to <strong>physics</strong> teaching
as interference phenomena using sound waves, which would need a special
sound-proof laboratory, or radio waves, requiring plenty of space in the open air.
Perhaps one of the finest teaching films ever made is that produced by EDC in
the United States showing cell division from a single cell of frog spawn, speeded
up by time-lapse photography: it shows superbly well something that could
never be seen by pupils using any technique other than film:seeing life begin like
this under a microscope is experience indeed.
Natural phenomena can be brought right into the classroom: wave motion on
the sea or shore can be used to supplement the ripple tank. A film about an industrial
plant or power station can amplify classroom work on energy conversions.
Animated diagrams in a film can also be a valuable technique if properly used.
but animated film of a rope moving up and down would be a ludicrous use of the
medium when it would be so much better to show a real rope (though this does
not mean that there is not great value in showing a film of wave motion along a
221 Films

eal rope or spring, especially when slow-motion projection enables detail to be
seen which it would be impossible to follow with the naked eye). There is a danger
in animation of the process building into the film incorrect information: all
makers of animated film know the problem of what colour to make an animated
electron! But wisely used animation can help pupils considerably, for example
in explaining the working of an electric motor, the movement of electrons
through a Franck-Hertz tube when studying energy levels or the principles of
the Hall effect.
The use of historical films also has a place in <strong>physics</strong> teaching, for example to
bring Einstein or Rutherford or Bohr to life at the appropriate stage of the teaching.
Historical films of this type are unfortunately scarce, but efforts might be
made now and in the future to increase their number: a film showing the first
Soviet Sputnik being launched would fall into this category. It is likely to have
been filmed and it would be helpful if a short-length educational film were available.
There is also a danger in any film that is designed to inform that it may do so
in such a way as to stifle critical thought: the professional commentator with perfect
diction, who appears to know all the answers, does not encourage active participation
by the pupil. Some of the P S S C films set a new standard in this respect
and the discursive style of the scientist in the film achieves what the dead-pan
voice of the professional fails to do : P S S C films almost invariably lead to discussion
in a way that many elaborate films produced by industrial firms never
achieve.
Films can make a valuable contribution in the teaching of techniques. Such
films can be useful as time savers whether they are about how to use micrometer
screw gauges or slide rules, the techniques of glass-blowing or soldering, how to
use various instruments or how to handle radioactive materials.
Fourthly and finally, films can play a very valuable part in the in-service
training of teachers. Such films have been used extensively in the United Kingdom
when introducing the Nuffield Physics Project. Teachers needed to learn
how to handle the new apparatus in the manner intended, and it was impossible
for the organizers and team leaders to attend the very large number of in-service
courses held throughout the country, but their low-cost films for teachers,
sponsored by Esso Petroleum, enabled the originators of the experiments to be
present, in film,on the courses. There was a further powerful advantage in that
Esso made the films available on free loan to teachers in their own <strong>school</strong>s: a
teacher lacking confidence could show himself the film and be teaching the
material shortly afterwards. Of course the details were all written up in the Nuffield
literature, but the visual impact is always an effective one. To quote one
example, the Nuffield project introduces the use of cheap oscilloscopes much
earlier in their secondary-level course than is traditional ; there were plenty of
teachers apprehensive about the best method of using them and the film for
teachers on this theme gave them confidence. Such films can be a powerful tool
in the implementation of new programmes.
222 Audio-visual <strong>Teaching</strong> Materials

15.5.2 The hardware
Motion pictures for theatres are on 35 mm film. Some educational films are
photographed on this stock and then reduced to the 16 mm or 8 mm format, but
the majority of educational films are now initially photographed on 16 mm film
and subsequently processed for projection on either 16 mm or 8 mm film.A new
8 mm film with smaller sprocket holes than the old and yielding a 50 per cent increase
in picture area has been introduced under the name ‘super-8’. It may
eventually replace 16 mm film in many educational uses.
Ten years ago most educational films were medium length (10-15 minutes),
16 mm black-and-white films with an optical sound track. The 16 mm projector
is still the universally accepted standard but many films are now in colour and
some use magnetic sound recording. Some of the newer projectors (both 16 mm
and 8 mm) are ‘self-threading’; it is only necessary to insert the film into a slot
and push a button and the film threads itself automatically, thereby getting over
the tiresome process of threading a film manually through the projector.
15.5.3
The production of amateur teachingJilms
The advent of inexpensive 8 mm.and super-8 cameras and projectors for home
movies makes it possible for teachers to produce their own teaching films.As
with slides, we have here a medium that can be exploited. at least at the start, with
very little in the way of equipment and experience. In the process teachers will
not only be forced to understand their subject matter better but they may discover
that it is a very pleasant and rewarding activity. Shooting directly on 8 mm
film can produce very professional looking results if good equipment and proper
editing procedures are used. It is not usually possible to obtain good copies from
the 8 mm original, but if they are likely to be needed the original should be shot
on 16 mm film.
Amateur films can provide an excellent basis for a professional retake. For
professional work it has been found that collaboration between scientist, teacher,
students and professional technicians such as directors, producers, scriptwriters
and camera-men is essential. And, of course, even a good film wil not be
widely seen unless there is an adequate distribution system. The amateur who
thinks about going professional should be warned that it is an expensive business.
Nevertheless it bears repeating that the amateur use of 8 mm cameras and projectors
should be encouraged. It is a medium in which one can begin with very
little in the way of equipment and experience and still produce software that combines
content, imagination and relevance to the curriculum - ingredients without
which even the most sophisticated hardware is ineffective.
15.5.4 Conclusion
There is no doubt that films are useful and wil always find a place in the classroom.
They can be formed into libraries, distributed to <strong>school</strong>s over an entire
country and used again and again. But there are also disadvantages.
223 Films

They must be shown in a darkened room, they cannot be interrupted easily,
and they have to be rewound before being replayed. No matter how learned and
competent the man on the screen may be, the teacher loses control of the logical
thread of his own presentation when he interrupts it to show a film.Furthermore
the competent teacher does not always like to be replaced for twenty or thirty
minutes of his class period. In addition the films are usually too expensive for
<strong>school</strong>s to build up their own library and this leads to all the inconvenience of
having to borrow films.
There appears to be a need for a medium which incorporates the advantages
of 16 mm films and yet dispenses with the handicaps. Loop films in cassettes are
probably the answer to this and are considered in the next section.
15.6 Film loops in cassettes
Advances in film and projector technology have made it possible to load three to
five minutes worth of 8 mm or super-8 film as a continuous, never-ending loop
into a cartridge, usually called a cassette, that can be rapidly inserted into or
removed from a special projector. As with slides, the image may be reflected
from a screen in a darkened room or it may form an image by rear projection
through a translucent screen so bright that little or no darkening of the room is
necessary. However the greatest advantage which film loops have is accessibility.
The loops are continuous and can be repeated as many times as desired. Each
film is short, presenting a single concept for the student to grasp, and it can be
used in the classroom, discussed, used again, and so on until the concept is appreciated.
They can be interrupted easily, as and when the teacher wishes. By comparison
with 16 mm films they are relatively cheap enough for each <strong>school</strong> to
build its own library. They are so simple to use in a classroom that a child can
load the projector, start it and stop it. They can be used with the class as a whole,
or by the individual pupil during periods of private study and revision.
The teacher can use them as an illustration in his own presentation of the topic
and he can provide his own commentary to suit the level of the pupils concerned.
Some loops can be shown to students of different levels all the way from <strong>school</strong> to
university, provided the explanation is of the proper level. When a large, vibrating
soap fdm is shown to a child, for example, his attention can be drawn to the
colours, to the patterns and the rhythm of the vibration. When the same film is
shown to a graduate student in <strong>physics</strong>, on the other hand, the language of normal
modes and eigenfunctions can be used.
If sound is necessary it can be supplied separately by the teacher recording his
own commentary on a portable solid-state magnetic tape recorder. Alternatively
it is possible to have a magnetic sound track on the super-8 film loop, which then
requires a special sound projector. The silent projector costs about $100 in the
United States and the sound version about $400, compared with a 16 mm sound
projector costing between $500 and $800.
The advantages of the silent film loop, or the super-8 film loop with sound,
over the longer 16 mm films does not mean that the latter are unimportant. In the
224 Audio-Visual <strong>Teaching</strong> Materials

first place, in order to produce duplicates, the original footage for 8 mm films
has to be photographed on 16 mm film.Film loops could, therefore, be made
available in 16 mm form to the many institutions round the world which do not
yet have access to the 8 mm loop projectors. In large auditoriums it is preferable
to project even the short silent films through a 16 mm projector.
15.7 Adding sound to visual techniques
The advent of the modem tape recorder has made the addition of sound a very
simple matter which can enhance teaching with slides, film strips, transparencies
for an overhead projector or silent film loops, whether used in the classroom,
lecture room or for private study.
The range of cost of magnetic sound recording and playback equipment exceeds
even that of optical cameras and projectors. Magnetic tape recorders and
playback combinations range all the way from under $30 to over $3000. With a
reel-to-reel tape recorder in the $500 class the fidelity of the sound recording and
playback possible today is truly remarkable. It is probably correct to say that it is
easier and cheaper to obtain high-fidelity sound reproduction than comparable
visual reproduction. Sound amplifiers that can handle frequencies from 20 Hz
to 20000 Hz with little distortion are quite common. The weakest links in a good
sound system are often the microphone and the loudspeaker, and particular
attention must be given to their choice if a natural reproduction of the spoken
word and of music are desired.
We would encourage teachers to experiment with home-made sound recordings
as teaching aids, as we did with home-made 35 mm slides, overhead transparencies
and home-made 8 mm motion pictures. Sound can be an effective
complement to sight.
The newest member of the tape-recorder family is the cassette tape recorder and
player. Many good models are available for less than $100. The tape comes in
loaded cassettes that can be inserted into the machine with even less difficulty
than putting a disc on a record player. They can be erased and re-used. Most
cassette tape machines use solid-state circuitry, are battery-operated, very small
and completely portable. They can carry up to two hours (one hour on a side) of
lectures, music or other sound. The quality of the sound that comes out of the
built-in loudspeaker is not of high-fidelity standard but it is usable in restricted
applications. At best it resembles the quality of a good portable radio. It is possible,
however, to connect the electrical output of the tape player directly to a
high-quality amplifier and speaker system (by-passing the built-in amplifier and
speaker) to obtain sound of intensity and quality that is almost as good as that of
the best high-fidelity systems.
Consider what this means. It means that recorded speech can be delivered from
a portable player to an auditorium that seats five hundred or more with a clarity
that far exceeds that of a lecturer speaking without the aid of amplification. It
also means that the voices of other speakers, such as those of eminent scientists
lecturing in their own special subjects can be brought to the classroom. It means
225 Adding Sound to Visual Techniques

that a student teacher can hear himself practice-teaching and that a master
teacher can record error-free sound tracks to go along with slides or overhead
transparencies.
All of this can be done with any tape recorder, but the special virtues of the
cassette tape recorder will probably make it one of the most useful audio aids of
the future.
15.7.1 The autolecture
An interesting innovation has been tried out by A. V. Baez at Harvard University.
He writes of it as follows :
An autolecture consists of a carefully prepared set of about ten transparencies for the overhead
projector and a thirty-minute lecture recorded on magnetic tape. The tape is coded
for stops during which student participation is elicited in the form of questions posed on
the partly exposed transparency. The moderator of the class, who may be a teaching
assistant or even an advanced student, stops the tape while the students respond in writing,
if they are called upon to do so, or to engage the students in a discussion to clarify some
points in the autolecture. The cues for action are all on the tape and they may even call for
the showing of a short film or the observation of a demonstration performed by the
moderator. If the moderator is a teacher with considerable knowledge of the subject but
limited teaching experience he can stop the tape whenever he can explain the subject
matter better than it was explained on the tape or he can stop the tape to answer questions
raised by the students. It is very easy to fill a fifty-minute period this way even though the
tape lasts only thirty minutes. It has been found useful as a means of freeing some of the
professor’s time, either for the preparation of demonstration lectures or for meeting
students individually. It has also been helpful in guiding teaching assistants to become
better teachers and lends itself readily to individual self-instruction and review.
This use of audio-visual material has possibilities, especially in those countries
where there is a shortage of adequate <strong>physics</strong> teachers.
15.8 Radio and television
When used in conjunction with carefully prepared written material, broadcasts
by radio or television can be extremely helpful. It would seem that television is
more desirable than radio, especially in developing countries where pupils can
clearly grasp for themselves concepts which are initially entirely unfamiliar.
Such systems are already successfully operating at <strong>school</strong> level in many countries,
including India, the Philippines and Nigeria. Again it should be stressed that
such systems do not make the teacher redundant, but they do change his role
somewhat. After each lesson the pupils will have absorbed differing amounts and
it is the teacher’s responsibility to have all the children ready for the next lesson.
Ideally he should also act as a <strong>source</strong> of material for the brighter pupils who wish
to pursue further what they have learnt.
In the more advanced countries television programmes can be an asset for
enrichment, especially if carefully prepared in association with a given teaching
programme. The difficulty lies in the times of broadcasts not fitting in with the
226 Audio-visual <strong>Teaching</strong> Materials

est of the <strong>school</strong> curriculum. This situation may change with the advent of
videotape recorders (VT R), but such equipment is extremely costly.
A useful development for the storage and playback of audio and visual
material is the electronic videorecorder (EV R) and its many competitors,
which wil convert an ordinary TV receiver into the equivalent of a home-movie
projector and a screen. The viewer can play the programme (or lesson) of his
choice by inserting a special cartridge, loaded with a new kind of film,into a
special playback unit which sends audio and visual signals into the TV set.
A seven-inch cartridge can play up to thirty minutes in colour or one hour in
black-and-white. The cost of the apparatus is considerably less than that of home
videotaping systems. A single unit, for example, could serve all the TV receivers
in an entire <strong>school</strong>, or individual receivers could be equipped to view different
programmes at a time chosen by the teacher. But this kind of equipment is at
present in its infancy and there are more urgent requirements for the consideration
of those developing new <strong>physics</strong> programmes in countries throughout the
world.
No reference has been made here to closed-circuit television. This has of course
proved valuable in university teaching, provided that a special programme has
been produced and that the camera has not merely looked in on a conventional
lecture. But at the present time closed-circuit television is not likely to contribute
greatly to <strong>physics</strong> education throughout the world at the secondary level. The
money for it can be spent in more effective ways except in certain sophisticated
<strong>school</strong>s.
Such however is the potential of television in the teaching of <strong>physics</strong> to large
numbers that it seems appropriate to end this chapter with an account of important
work done in New South Wales, Australia, which suggests exciting possibilities
for the future. The following account is provided for this book by C. B. A.
McCusker .
15.8.1 The use of television in the teaching of<strong>physics</strong>
Television offers major advantages in the teaching of <strong>physics</strong> in secondary
<strong>school</strong>s. If the same programme is available throughout a single state or country
it provides teaching of a uniform standard throughout that area. The standard
can be made very high since the best teachers available can be used and they can
spend much time and money on each lesson. Experiments can be demonstrated
which would be too expensive or large or difficult to do ‘live’ before a multitude
of classes. Experiments which are too small to show live to a class can be demonstrated,
for instance the demonstration of Brownian movement through a microscope.
Diagrams of apparatus and mathematical derivations can be shown using
material prepared by competent graphic artists. Films of large-scale physical
experiments, for example experiments using high-energy accelerators, can be
incorporated naturally into the lesson. So far these advantages have not been
realized on a large scale. This section combines an account of a complete firstyear
university <strong>physics</strong> course on videotape which has been made in Sydney with
227 Radio and Television

a description of the DAE-NASA satellite ITV experiment in order to show
the possibilities that already exist for the nationwide teaching of <strong>school</strong> <strong>physics</strong>
(and indeed of many other subjects).
In 1962 the state of New South Wales began a new secondary-<strong>school</strong> course.
This was a six-year course (previously a five-year course) with completely new
syllabuses in all subjects. The first students from this new course reached the
universities in February 1968. To meet the new requirements, the <strong>physics</strong> department
prepared completely new courses. About 1500 students take first-year
<strong>physics</strong> each year. These were divided into A- and B-streams. Students in the A-
stream were those who expected to major in <strong>physics</strong> or allied subjects (physical
chemistry, applied mathematics, electrical engineering and so on). All other
students, including students taking only one year of <strong>physics</strong>, were in the B-
stream. Each year about 250 students begin the A-stream. The A-stream students
are given normal lectures on the established university pattern. For the B-stream
students a new type of course was prepared. This consists of three parts. The first
is a modern practical course of three hours per week in which the students do
‘open-ended’ experiments using linear air tracks, lasers, ultrasonics and so on.
The second part consists of seventy-eight lectures, each of about forty-five
minutes, recorded on videotape and transmitted on closed circuit to lecture
theatres equipped with television receivers. The third part is a system of voluntary
tutorials to supplement the lectures and to assist the students in problem solving.
Some of the students entering the course are well-equipped with both <strong>physics</strong> and
mathematics. Some are not. As a result the standard of the course overlaps somewhat
with the final-year <strong>school</strong> <strong>physics</strong> course for those who hope to major in
<strong>physics</strong> at the university. The course of television lectures has already been used
for the ‘in-course’ training of secondary-<strong>school</strong> <strong>physics</strong> teachers.
The production of such a course of lectures was made possible by the prior
existence of the Sydney University Television unit. This unit (in conjunction
with the School of Biological Sciences) had already made a seventy-eight lecture
first-year biology course which had been notably successful. The staff of the unit
consists of a director (who is also a producer), another producer, an assistant
producer, seven technicians under a technical supervisor, four graphic artists and
two secretaries. They havp a well-equipped (but rather small) studio and an excellent
outside-broadcasts van. The replay section has four videotape replay
machines which can transmit to any or all of eight lecture theatres. The total outlay
in setting up this system was about $500000 A.
The seventy-eight <strong>physics</strong> lectures were given by a total of eight physicists from
the staff of the School of Physics. For about thirty of the lectures two physicists
combined, and discussion between them was consciously used as a method of
instruction. This ‘combined lecture’ was found to be a very satisfactory method
of presentation. An average lecture contained jve demonstration experiments,
thirteen graphics and one film extract. Each lecture took the physicist between
eight and forty hours work (depending, largely, on their previous experience with
the medium). Detailed lecture notes were prepared and sold to the students at
cost. The response of the students was carefully monitored by questionnaires and
228 Audio-Visual <strong>Teaching</strong> Materials

y having the currently appearing lecturer attend mass tutorials to answer student
questions.
The experience of the Schools of Biology, Physics and Psychology has shown
that it is possible and, if done well,desirable to give these mass lecture courses via
television. The D AE-NASA experiment makes it seem likely that this system
could be extended to <strong>school</strong> teaching over a complete nation or state. This experiment
is a cooperative venture between the National Aeronautical and Space
Agency of the United States of America and the Department of Atomic Energy of
India. The venture began with the signing of a Memorandum of Understanding
in September 1969. The experiment wil use an ATS-F satellite in a synchronous
orbit over the southern tip of the Indian subcontinent. Instructional programmes
wil be beamed to the satellite which wil re-transmit on a frequency of
860 MHz to 2000 augmented-type television receivers disposed in four clusters
of 500 each. These clusters wil be located in different parts of India chosen to
give the maximum possible information on the operation of the system. In addition
there will be some ground transmitters which re-broadcast programmes
received from the satellite to their local areas (generally of high population density).
The initial instructional programmes wil be directed towards (a) familyplanning
objectives, (b) teacher training and other occupational skills, and (c) the
improvement of health and hygiene. The satellite is planned to be launched in the
second quarter of 1972 and from 1974 to 1976 it is hoped to add between 100000
and 150000 (mainly communal) television receivers to the system each year.*
So it is obviously possible to broadcast a complete course in <strong>physics</strong> (and indeed
many other subjects) to an entire continent, if need be. In India there wil be
some difficulties with the various languages. For monolingual areas such as the
greater part of the North and South American continents, Australia, large areas
of the US S R or Japan this difficulty does not arise. The system envisaged would
consist of half-hour televised lessons (made by the best available teachers and
expert production crews) followed by explanatory discussion sessions conducted
by the local teacher. Suitable notes would be prepared both for students and
teachers. Since the number of videotapes, even for a year’s course, is quite small,
the system is inherently flexible. It provides uniform minimum standards
throughout the area. It greatly reduces the labour of teaching science and gives
the individual teacher more time to devote to his subject and to the individual
children. The Indian studies suggest that it is by far the most economical method
of instructing a large audience. It seems that in some parts of the world this combination
of television teaching and the benefits of space research may revolutionize
the teaching of <strong>school</strong> <strong>physics</strong> in the very near future.
* Vikram Sarabhai. Chairman of the Indian Atomic Energy Commission very kindly supplied this
detailed information on the DAE-NASA scheme.
229 Radio and Television

15.9 Conclusion
Both visual aids and audio-visual aids have much to contribute towards <strong>physics</strong>
education, as they have to all science education. At present there is more hardware
available than the software to go with it and there is therefore much scope
for international cooperation in a medium in which development of material is
always costly both in time and money. As Professor Ootuka of Japan has said,
the process of teaching <strong>physics</strong> will never be as efficient as it might be until good
aids are generally available throughout the world.
230 Audio-visual <strong>Teaching</strong> Materials

Part Six
Towards Curriculum Reform

16 Mechanisms for Curriculum
Reform
This edited chapter is based primarily on contributions written by John Lewis and Stephen
Winter, but it draws also from a Unesco paper on national science-teaching improvement
centres (Unesco, 1967). There can be no standard pattern for curriculum reform as so much
depends on local conditions. The situation in the U SA, where there can be a very large
number of different curriculum-reform projects based on different universities, is quite
different from the situation in say East Africa, where it is desirable for the three countries
Kenya, Tanzania and Uganda to cooperate. The pattern suggested in this chapter is
directed more at a singlenation which is setting up its one and only science-teaching
improvement centre as a medium for reform. It is hoped nevertheless that the ideas and
suggestions contained in the chapter will have wider application as well.At least the
comments are based on the experience of science-teaching reforms in many different parts
of the world.
16.1 Background
The deep changes produced by science and technology in man’s daily life are
perhaps nowhere more disturbing than in the area of education. These changes
threaten to reduce learning in <strong>school</strong>rooms and university lecture halls to an
exercise in irrelevance for the students: the gap between what they learn and what
they need to know to cope with the world they are about to enter grows constantly
wider.
The peril in <strong>school</strong>ing which loses touch with the world in this way is not simply
that too few scientists or engineers wil be produced for the needs of science and
technology. This shortcoming does to be sure seriously retard industrial and
technical development. But the much greater peril of obsolescent <strong>school</strong>ing is its
failure to prepare all students, whether they be future engineers, statesmen,
labourers or clerks, for life in a technologically orientated society.
There is almost universal international acceptance of industrialization as the
route to a better life. To reach and sustain the goal of industrial power a nation’s
citizens must embrace technology and science, and the ways of thought associated
with them, as the principal agents for change and as the means for removing
poverty, disease, hunger and ignorance. Where but in the <strong>school</strong>s of a nation can
such widespread public trust in the usefulness of science be nurtured? The <strong>school</strong>
must weave into the very texture of the thinking of each pupil a comprehension of
233 Background

science and technology: how these have arisen in human history, what human
drives they represent, what power and what limits they contain.
Fortunately teachers, scientists and government authorities of many countries
do understand the peril to their continuing economic and social progress of allowing
<strong>school</strong>s to slip further into obsolescence. The appreciation of the need for
curriculum reform is now widespread and this chapter attempts to suggest
mechanisms by which it can be realized, together with some warnings about
possible difficulties that may arise.
The curriculum reform discussed here is directed at improving the quality of
science education. In this respect it is concerned with the long-range solution of
science-teaching problems rather than the short-range or ‘crash’ programmes
that Unesco and other agencies are mounting in attacks on the alarming quantitative
needs of education: the lack of <strong>school</strong> rooms and laboratories, the paucity of
printed text<strong>books</strong> and suitable science apparatus, and the shortage of trained
science teachers. The possibility exists, however, that the long-range projects for
reform will lead to sufficient improvement in the quality of education to eliminate
some of the quantitative problems. No nation, for instance, seems likely ever to be
able to train all the qualified science teachers it really needs. But new long-range
curriculum reform can do much to enable indifferent teachers to achieve a
standard through carefully designed teaching materials.
16.2 Initiation of reform
Concern for revision of existing science-teaching programmes usually develops
from one of four groups. Officials in a ministry of education may wish to introduce
into the <strong>school</strong>s of the nation some of the ideas produced by the world-wide
science-curriculum reform movement. It may be the scientists of the nation,
whether in universities, government service or the private sector of the economy,
who find that <strong>school</strong> programmes have failed to keep pace with the rapid changes
in the sciences and are in need of modem ideas. It may be officials in a national
planning office who find that the goals set for social and economic development
place demands on the <strong>school</strong>s for scientifically and technically trained manpower
in excess of the <strong>school</strong>s’ capability to produce it. Finally, it may be the teachers
themselves who are conscious that what they are teaching is outmoded, that their
techniques are inefficient or inadequate to produce children who will think for
themselves and are properly equipped for the society in which they are growing up.
Once the decision is made to establish a new science-teaching programme in a
particular country, it is essential for its ultimate success that there should be wide
local involvement.
16.3 Local involvement
Wide local involvement will increase the number of those who can contribute to
the programme and help substantially in its ultimate implementation. As will be
stressed below, planning for ultimate implementation must be considered even in
the initial stages of curriculum reform.
234 Mechanisms for Curriculum Reform

The ministry of education, as the prime body responsible for the education of
the children, must necessarily play an important role. It wil be desirable for the
inspectors and <strong>school</strong> managers appointed by the ministry to feel involved in the
new developments.
The universities have much to contribute through their scientific staff, both in
stimulating the teachers involved in the development work and ensuring that the
kind of science being taught in the new programmes is relevant to the science of
the second half of the twentieth century. It is the task of the scientists to clarify and
interpret the goals of modern science instruction and to monitor the appropriateness
of the materials developed by the reform effort. Expert advice can also be
obtained from sociologists, psychologists and others within the universities.
It is essential that good teachers be involved with the development work from
the start of the programme. It must not be forgotten that it is for the teachers that
the programmes are being produced; they are the medium through whom the
pupils wil benefit. The good teacher has much to contribute through his intimate
knowledge of children and how they react. Furthermore, the active involvement
of practising teachers wil give considerable psychological encouragement to other
teachers when it comes to the implementation stage: the new programmes will
appear less like something imposed from above.
As one of the ultimate recipients of the product of the <strong>school</strong> system, the needs
of industry must be considered. Industry can also provide an expertise which will
help to ensure that the science taught is relevant to the world outside the classroom,
and will help the programme to include reference to some of the applications
of science which show that relevance. The assistance that industry can give
in providing equipment should not be overlooked.
Ministries other than the ministry of education, for example the ministries of
food and agriculture, can also contribute profitably to a new programme, in
particular a ministry of agriculture in a country which is basically agricultural.
Recearch organizations and technical institutions can provide expert help in
much the same way as universities. They can help to ensure that science programmes,
especially at the secondary level, are relevant and up-to-date. Furthermore
technical institutions may have a particular contribution to make when the
stage of developing or manufacturing simple apparatus is reached.
Finally there are teachers’ training colleges to be involved. The experience of
those who teach at these colleges must not be overlooked. Their contribution at a
later stage, when it comes to implementation, wil be so important that they must
be involved from the start. One cannot stress too much the importance of letting
people feel that they are involved: the ultimate implementation wil be greatly
eased if those concerned with it feel that the programme is their own programme
and not something imposed from outside.
16.3.1
A steering or consultative committee
How is the involvement to be realized? One possible method is to establish a
steering or consultative committee for the project and to include representatives
from all the above interests.
235 Local Involvement

The size of such a committee may seem at first sight to be a little daunting, but
under wise and tactful chairmanship, perhaps at ministerial level, it will enable all
the above to feel involved.
16.4 Provision of funds
Curriculum renewal demands three kinds of re<strong>source</strong>s : money, manpower and
ideas. Each is scarce. Ideas can be borrowed from the experience of others without
depleting the reservoir, but money and manpower devoted to curriculum renewal
cannot be used for other national tasks. Decisions to allocate them to the programme
must be made within the entire framework of national priorities. Any
national planning office must therefore be continuously appraised of needs and
achievements to justify continual investment in curriculum reform.
An essential requirement for designing programmes is that adequate funds
should be available for the work that will be necessary. Furthermore, there is no
point in embarking on a development programme if adequate funds are not likely
to be available for its ultimate implementation. Curriculum reform is not just a
fashionable academic exercise. It must lead to the use of the programme in the
<strong>school</strong>s. The availability of funds for implementation must therefore be considered
at an early stage, especially as it will be necessary to design the programme
to match the re<strong>source</strong>s that the country will ultimately be able to provide for
implementation: the coat must be cut according to the cloth available. It is
absurd, for example, for a new programme to require the use of a high-voltage
power supply unit if there is no possibility of every secondary <strong>school</strong> having such
a unit available.
Whereas funds may be made available from United Nations agencies to stimulate
initial developments, it cannot be expected that these agencies will be able to
finance more than a limited number of pilot projects, and in no case can they be
responsible for providing the necessary funds for implementation. It is therefore
essential that the maximum use be made of local re<strong>source</strong>s and that there be as
little dependence as possible on foreign-currency needs.
Having stressed the importance of providing adequate funds, there is one
bright aspect. As more and more curriculum development work is done throughout
the world the cost of projects will become progressively less as new ones are
able to benefit from the development work and experience of others.
16.5 Establishing a science-teaching programme
16.5.1 The leader or director
The identification and appointment of the leader for a project (leader, organizer,
project director, the name is immaterial) is the most important of all tasks, for the
success or failure of the programme may depend on him. Whenever possible the
leader should be someone from the country concerned as he will have a more
intimate awareness of the needs of the country, of its cultural background and of
the pupils for whom the programme is intended.
236 Mechanisms for Curriculum Reform

Occasionally it may be better to appoint an expatriate leader. He has the advantage
of having no other commitments in the country and he can devote himself
full-time to the project. Furthermore he brings a fresh point of view and is usually
stimulated by the new problems. On the other hand, if he has already been involved
in leading the development of a new programme in a more highly developed
country, he may be too imbued with its ideas and wish to introduce too much from
it into the new programme. It may therefore be wiser to use the expatriate as an
expert consultant rather than the actual leader of a new national programme.
In some countries it may be desirable to appoint a single leader for all science
education. In others it may be better to appoint separate leaders for primary and
secondary programmes. For secondary programmes it may be desirable to have
separate leaders for <strong>physics</strong>, chemistry and biology. Some countries may prefer to
consider the possibility of an integrated science programme (see chapter 8, in this
volume, on Integration).
Whoever is appointed leader must have the technical competence to lead the
efforts of the project, the personal qualities to inspire all those associated with it
and the ability to weld everyone into a productive team working for the common
good of the children in the country.
16.5.2 Science-teaching improvement centres
Once the leader is appointed it is essential to establish a centre which can be the
headquarters for the development work. Such a centre wil have a variety of
purposes.
(a) It wil provide the place where development work can be done. including the
necessary administrative work.
(b) It will provide a meeting ground between teachers and teachers, between
teachers and university representatives, between teachers and the development
group and outside experts. It wil rapidly become a focal point for meetings of
local teachers, and of national or regional groups.
(c) It will be a place where new ideas can be discussed, where new equipment can
be seen and studied, where apparatus can be developed. There should be workshop
facilities, equipped for the assembly of inexpensive laboratory kits. It should provide
library facilities, including a centre in which the best of new science-teaching
materials from many countries wil be on display. There should be a film library
and facilities for viewing all forms of visual aid; there might even be facilities for
making 8 mm films.
(d) It might with advantage become a centre from which the more expensive
items of equipment can be borrowed for <strong>school</strong> use.
This science-teaching improvement centre should probably be situated at a
university, or perhaps at a research institute. The work can only be done successfully
with the full participation of first-rate scientists, so proximity to the university
has obvious advantages. At the same time, tailoring new ideas to fit actual
237 Establishing a Science-<strong>Teaching</strong> Programme

conditions in <strong>school</strong> classrooms necessitates full participation by experienced
teachers and the centre should be suitably situated for as many of them as possible.
Although there must necessarily be one administrative headquarters for the
main development work, separate centres are possible for parts of the work: a
centre, possibly housed in a faculty of education, might concern itself with the
necessary evaluation work, developing appropriate means for evaluating pupil
progress and determining the effectiveness of the new materials as a means of improving
science teaching; other separate centres might be concerned with teacher
training and retraining or with the production and distribution of the new
materials. The teacher-training effort might be in a faculty of education or a
teacher-training institution. The production and distribution centre might be in a
technical <strong>school</strong> or college with high production capabilities.
It is however impossible to generalize over the organization and nature of such
centres. All will depend on local or national circumstances and no standard pattern
is likely, or even desirable. What is desirable is that each country should have
its own science-teaching centre. In the initial stages it may be necessary to have
regional centres, as for example the Regional Centre for Education in Science and
Mathematics (RE C S AM) in Penang, Malaysia, which coordinates the needs of
Indonesia, Malaysia, Philippines, Singapore, Thailand and the Republic of
Vietnam. Such regional centres can do much to coordinate the activities in the
countries involved as well as to encourage national centres to be set up in those
countries. In large countries like India it may be necessary to have two, three or
more centres in different areas.
16.6 Plan of operation
Curriculum renewal proceeds in two distinct stages from the time the decision is
made to reform part of the teaching programme to the time when the programme
is adopted for general use: a development stage and a training and implementation
stage. While these stages require different kinds of thinking and professional
competency, they are part of a continuous process. Both parts are of concern to
each other, and initial planning must have the whole continuum in view.
The development stage begins once the leader is appointed and the centre
established. It ends when the reformed programme has undergone testing in a sufficient
number of varied classroom situations for a long enough period of time to
show that it is effective and practicable and that it meets the reform objectives.
The development stage consists of the following steps:
(a) The decision to reform, the commitment of re<strong>source</strong>s and the setting up of an
organization.
(b) The clarification of objectives and the selection of the means to achieve the
objectives. Aims control methods, and methods control the syllabus. A syllabus
can be designed to promote methods and methods are chosen to promote objectives.
(c) Once the objectives are established, a project team should begin by examining
existing schemes which have already been tried out in other countries. It should
238 Mechanisms for Curriculum Reform

e realized that there is no ‘best’ programme from any relatively developed
country which should be slavishly followed. All overseas programmes (PS S C,
Chem. Study, CB A, the Nuffield projects, the Harvard Project Physics, etc.) were
designed for particular purposes in the countries concerned and are only likely to
be suitable for adoption in a very limited number of other countries. The P S S C
scheme, for example, was a relatively sophisticated one-year programme (though
it has been used as a two-year course) for American high <strong>school</strong>s where there is
usually a very limited background of mathematics: it is normally used in one
or other of the lasttwo years of secondary <strong>school</strong>, whereas many countries want a
programme extending over the whole of the secondary <strong>school</strong>. Likewise the
Nuffield 0-level course was designed for the age group 1 1-16 years and is intended
only for the top 30 per cent of the ability range in the United Kingdom. Furthermore
it makes use of certain sophisticated apparatus which it was right in the
circumstances of the UK to expect their academic secondary <strong>school</strong>s to have, but
this would not necessarily be the case in many developing countries. Even more SO
does this apply to the Nuffield A-level <strong>physics</strong> project, which is for use in academic
<strong>school</strong>s in the last two years of the secondary stage when the English system of
specialization has begun: much of the Nuffield A-level work would be appropriate
to university work in other countries where there is not the same degree of
specialization.
On the other hand, there is a considerable wealth of experience in those projects
and any country developing a new programme would be wise to make a careful
study of them first, both as a <strong>source</strong> of ideas and to avoid wasteful development
work which has already been done elsewhere.
(d) The development ojtrial classroom materials. Once the objectives are established,
existing material has been studied and the methods to be adopted to
achieve the aims of the programme have been decided, the production of the project’s
own material must begin. Decisions wil have to be made by those responsible
on what materials they wish to produce: they wil have to decide on (1) text<strong>books</strong>,
(2) teachers’ guides, (3) background <strong>books</strong>, (4)apparatus and the kind of
experimental work to be done, (5) films,(6) other visual aids and (7) examinations.
Whereas it is hoped that a modern scientific course would be based on experiment
and direct observation, the extent to which this is possible may depend on
the availability of laboratories. For this reason the implementation of the programme
must be constantly remembered throughout the development stage.
There is no point in recommending a piece of apparatus for use in the trial <strong>school</strong>s
if it cannot ultimately be provided for all <strong>school</strong>s.
Throughout this stage the closest involvement of teachers is essential. If possible
it might also be wise to involve some pupils, even before proper trials have
begun. This would initiate a continuing process of evaluation.
(e) Experimental or trial stage. There is little point in developing a new programme,
except as an academic exercise, unless there are extensive trials of the
material before it is adopted for general use. Limited trials in a few <strong>school</strong>s might
precede more extensive trials, and they should be conducted in <strong>school</strong>s of all
239 Pian of Operation

types: in rural <strong>school</strong>s, urban <strong>school</strong>s, <strong>school</strong>s with bright children and <strong>school</strong>s
where they are less able. Likewise both good and bad teachers should be involved.
Feedback should be required from all teachers involved. There should also be a
continuous process of evaluation throughout the trials : evaluation of the pupils'
progress and of the system as a whole and whether the objectives are being
achieved. In the light of this evaluation and feedback it wil be found necessary to
rewrite and redesign the material during the trials.
This trial stage is a valuable one, at which even the parents can begin to be involved
in the programme so that they appreciate its objects. Their involvement
wil be significant when it comes to implementation.
16.7 Time factors
As development projects wil always fill the time available and it is never felt by
those involved that the development is complete, it is strongly recommended that
national authorities should take into account the advantage of a time-limit(three
to five years) in the development of a programme. Such a time-limitneeds to be
established at the outset. This does not of course preclude a permanent programme
for continuing curriculum development, but experience with various
projects has shown the advantages when a sponsoring authority has insisted that a
programme must be ready for implementation in, say, four years.
It has been pointed out that there are many factors which may affect the rate of
change. The rate of change at any one stage may be controlled by factors quite
different from those controlling other stages. Analysis of such factors can save a
great deal of time and effort. It happens, for example, that one of the most significant
factors in the rate of programme development is that of secretarial services :
this can be solved by hiring more secretaries. In some countries the rate of change
in mass education is determined by dietiprotein deficiency) ; in others the training
of teachers at university level. Quite different design solutions are required in
each case. In many developing countries the rate appears to be determined by the
need to obtain enough freedom in the system of education for enterprising individuals
to try some simple new ideas. In some projects the rate is seriously impeded
by those involved in curriculum development not doing the work full time
but fitting it in with many other commitments. It may require effective action by a
consultative or steering committee to get over these difficulties.
16.8 The kind of course
Much that has been written above would apply to any curriculum-development
work. It certainly applies to science-teaching reform at both primary and
secondary levels. At the secondary level, however, certain decisions have to be
made about the nature of the course.
There is first the decision about the level of the course. Elsewhere in this volume
Dr Kothari argues that it is necessary to develop two types of course in India, one
for the able child to be taught in special <strong>school</strong>s, the other for the remainder. This
240 Mechanisms for Curriculum Reform

distinction has already been adopted by the Nuffield projects in the United Kingdom
: the Nuffield 0-level <strong>physics</strong>, chemistry and biology projects were written
for the top 30 per cent of the ability range, while the Nuffield Secondary Science
Project is being developed for the remainder.
There are also decisions to be made about whether separate <strong>physics</strong>, chemistry
and biology courses should be prepared or whether an integrated course is desirable.
There are the questions of how much history of science and how much
philosophy should be included in the programme; also the extent to which applied
science and technology should be included. These are decisions that every country
must make for itself, but it is hoped that the other chapters in this volume which
discuss these questions may help those concerned to come to their own conclusions.
16.9 Examinations
Existing examinations can be a serious obstacle to educational development. If a
child has taken part in a new programme in which the object has been to develop a
scientific attitude, affecting both his way of thinking and acting, he will not be able
to answer well a traditional paper which relies on rote memory. It is therefore
necessary that alternative examinations be set for those children involved in trial
programmes.
On the other hand new examinations can be an aid to good teaching and can
help effectively to bring about the objects of science-teaching reform. Unfortunately
their enthusiasm for curriculum reform sometimes blinds those involved to
the important role of examinations. It is essential that attention be given to
examinations at all stages of the development stage and it is necessary that national
governments accept that new examinations are vital to a new programme.
Examinations are discussed in greater detail in the following chapter.
16.10 Implementation
As has been repeatedly stressed above, planning for implementation, which wil
have to be financed largely from local or national <strong>source</strong>s, must be considered
throughout the development stage and is an essential part of it.
In the design stage the steps necessarily follow themselves in sequence. In contrast,
all parts of the implementation stage must occur simultaneously. When it is
time to begin the broad distribution of the machinery of curriculum renewal, all
components, <strong>books</strong>, laboratory materials, films.film loops and other audiovisual
material, must be available. This means that production and distribution to
<strong>school</strong>s must be planned and implemented well in advance. Furthermore, teachers
must be educated to use the new materials in the spirit of the new programmes.
Hence trainers of teachers must be enlisted in the effort early and guided to help
teachers. Opportunities for in-service training must be devised and teachers encouraged
to take advantage of them in time. A systematic effort to disseminate
information about the new programme must be instituted to advise teachers, administrators
and the public on the new programme. Al of these must proceed
241 Implementation

apace long before the conclusion of the development stage to ensure that the
<strong>school</strong>s and teachers are ready whep the course is. Nothing however is so important
as the inwlvement of the teachers who will teach the course, and this is discussed
in the next section.
It should not be forgotten that implementation is not the end. Curriculum
reform is a continuing process. Although it may be desirable to set a time-limit to
the development of an initial programme, there will be a need for continual modification
and further research. It is to be hoped that in setting up the development
centre this future need will also be remembered.
16.1 1 Involvement of teachers
Involvement of teachers is accepted as a sine qua non of all development work.
They should be involved with the science-teaching improvement centre and encouraged
to look on it as their centre. They should be involved with trials. They
can give encouragement to other teachers, and good teachers may themselves set
up other ‘ sub-centres’. There should be close liaison with teachers associations
which can do much to foster the ideas behind the new programmes.
Future teachers should not be forgotten and close links between the centre and
training colleges will do much to involve them. The proximity of the centre to a
university may result in students becoming involved and this may encourage some
better students to enter the teaching profession.
As already mentioned the training and retraining of teachers is an essential
part of curriculum reform and is discussed in detail in a separate chapter of this
volume. But there are also other factors which need consideration. There are few
nations of the world where teachers can function under truly professional conditions.
L. S. Kothari points out that in ancient India a teacher had the highest position
in society and a king would stand to welcome him; some Indian scriptures
even put a teacher before God! He says that unfortunately in India today there
are two important and very valid reasons why better people, who might inspire
their pupils, do not want to teach - low salaries and low status in society. He
adds that the greatest problem typically is salaries. There are few teachers in the
world whose earnings suffice to provide a standard of living commensurate with
their educational backgrounds and social contributions. Consequently, in many
parts of the world, teachers hold several ‘full-time’ jobs simultaneously in order
to accumulate a reasonable monthly income.
Nearly as serious as the physical and mental exhaustion produced by excessive
work schedules is the lack of facilities for teaching science. In some countries the
few <strong>school</strong>s that have spaces set aside for practical work are likely to have only the
most rudimentary laboratory tables or benches. They are inadequate for most of
the pupil experiments that accompany existing courses. Teachers are forced
therefore to focus on theory.
The importance of inducements to encourage teacher participation in curriculum
reform must not be overlooked. Such inducements might include upgrading,
financial increments, promotion prospects and prestige. It is essential that
242 Mechanisms for Curriculum Reform

national governments should-realize that teacher involvement is vital at all stages
of both development and implementation of new programmes, that teaching such
programmes can impose an additional burden on them and that funds must therefore
be available to encourage this involvement so that the pupils really benefit
from the development work that has been done.
16.12 One method of involving teachers
Perhaps a technique of involving teachers, which was used most successfully in the
United Kingdom, would be of general interest. In setting up the Nuffield 0-level
<strong>physics</strong> project it was accepted that teacher involvement was essential for the success
of the programme and for its ultimate implementation. Consequently the
team at work on it was not centralized, but various team leaders were appointed
based in different parts of the country, in Scotland, Newcastle, Leeds, Manchester,
Birmingham, Malvern, Bristol, Cambridge and London. Working in these areas,
usually, but not always, associated with a local university, these team leaders
brought together groups of prominent teachers, each group to work on one
particular part of the course, one on energy, one on waves and oscillations, one on
quantum phenomena, one on mechanics, one on examinations and so on.
At first sight this may appear an untidy way to do curriculum reform but the
advantages were considerable. Admittedly such dispersal added to the burden imposed
on the central organizers, but it increased substantially the number of
teachers and of university participants involved in the project. Bright ideas poured
in from all directions and even if only a proportion were ultimately used teachers
everywhere felt it was indeed a national programme and above all that they were
involved in it. It was certainly worth the extra inconvenience to the central
organization.
As the programme evolved these teams became centres for conducting regional
trials of the programme. Finally, when implementation began there were centres
already in existence for running in-service courses, and there was a large body of
men and women already committed and able and willing to help in the programme
of re-training teachers.
16.13 Summary
A successful effort to introduce science-curriculum renewal in any country must
fit into the overall planning for national development. It must concern itself with
all the factors that influence teaching in the <strong>school</strong>s, from the tangible facilities
and materials available to the teacher to examinations and such intangibles as the
confidence of teachers, gained through in-service training, and their professional
identification, gained through communication with other scientists and colleagues.
The production of new course materials, the beginning of the renewal effort are
thus but means towards a variety of improvements in <strong>school</strong>s and teaching.
243 Summary

17 Evaluation and Examinations
Examinations can play a vital part in deciding the kind of teaching that takes place in a
secondary <strong>school</strong>. However high the ideals of the designers of new programmes, the
success of the course in the eyes of many pupils, and in the eyes of most parents and many
administrators, will lie in the achievements or otherwise in the finalexaminations, illogical
though this may be. The aim of a course may be to strive for understanding or to encourage
pupils to apply their knowledge in unfamiliar situations, but if the finalexamination merely
asks for the recall of factual information, it wil not be long before much of the teaching
has lapsed into the imparting of such factual knowledge. On the other hand, good
examination questions can be a powerful instrument in further advancing the aims of a
project, giving encouragement to the teacher and pupil alike to pursue the course in the
manner intended.
But the evaluation of a science-teaching programme does not lie merely in an
assessment examination at the end of the course. There has been an increasing awareness
in recent years of the importance of evaluation as a continual process throughout the
development and implementation of new programmes. Unfortunately there is not yet
enough experience in thisfield of evaluation, but in this chapter are included two
separate contributions by men who have worked in this field.The first is by Leo Nedelsky
and the second by R. G. Munro. Although there is some overlap between the papers, it
would not be appropriate to attempt to edit them into a single contribution as has been
done elsewhere in this volume. The chapter concludes with some discussion of some
specifictypes of examination questions in <strong>physics</strong>.
17.1 Evaluation of a programme of training
L. Nedelsky
The proper function of evaluation is to help make plans for the future and to estimate
their probable cost and success. This section discusses evaluation primarily
in so far as it can identify those modifications of a given programme of training
that wil spell its success in the future. Ideally, modifications should vary from
<strong>school</strong> to <strong>school</strong>. Even though our goal is prognosis it has to be based on the
diagnosis of the present success of the programme and of the improvement over
the past. The following indices of success are essential for both diagnoses.
(1) The children have attained the important academic objectives.
(2) <strong>Teaching</strong> and examinations are appropriate for the academic objectives.
244 Evaluation and Examinations

(3) The goals of the programme are acceptable to the <strong>school</strong> (teachers, pupils.
administrators) and the community.
(4) The <strong>school</strong> work is interesting to teachers and pupils.
(5) The teachers do educational experimentation and use its results.
(6) The programme has had to work under difficult conditions.
(7) The efficiency of the programme is high: the cost in time, energy and money is
well justified by the results.
A proper diagnosis requires an evaluation of the following stages of development:
(i) the design of the programme, (ii) the programme in action. (iii) the
results of the programme.
Criteria for evaluation may be expressed as questions to be answered. In
evaluating the design of the programme, the following questions must be
answered :
(a) Does the programme have valid objectives?
(b) Does it have a usable description of the relevant pedagogy and examinations?
(c) Does it have a written plan for evaluating the success of the programme?
(d) Does it have a written plan for explaining points (a), (b) and (c) to the participating
<strong>school</strong>s ; for modifying the programme to fit various <strong>school</strong>s; for helping to
put the programme into practice?
In evaluating the programme in action, the questions are:
(a) How well is the programme understood and accepted?
(b) Do the participants have competence and desire to pursue the programme?
(c) Do they use appropriate pedagogy and examinations?
(d) How easily and how extensively has the programme been modified to meet the
requirements of (a), (b) and (c)?
In evaluating the results, the questions are:
(a) To what degree are the indices of success (1)-(7) present?
(b) What are the factors that favour or hinder the programme?
(c) What has been the cost of the programme?
(d) How do (a), (b) and (c) compare with the past of the <strong>school</strong>? With other
<strong>school</strong>s ?
(e) What is the next step: abandon the programme. continue it, modify it? If the
latter. what modifications are essential?
17.1.1 Evaluating the design of the programme
Design of the objectives. A programme of training should help change the child
into an adult who wil function well in his society. To be useful to educators this
245 Evaluation of a Programme of Training

assertion has to be translated into more academic objectives. In a science programme
the objectives should specify the content, that is the subject-matter to be
studied and the behavioural objectives, that is, what the student is to be able to do
with the content. He may have a knowledge of it, that is, be able to repeat or imitate
what he has read, heard, or seen done. He may have an understanding of the
content, that is be able to apply his knowledge in new situations, situations that
are different from those in the textbook and those explained in class. He may have
acquired the ability to learn by himself, that is without a teacher’s aid, from <strong>books</strong>
and experience. Finally, he may have acquired certain desirable attitudes and
habits.
It seems generally agreed that understanding and ability to learn should be the
central objectives. They clearly look toward the pupil’s future life, for he will have
to deal with non-academic problems without a teacher’s aid. The attainment of
these objectives also correlates well with future academic success. For these reasons
they can command the <strong>school</strong>’s and community’s respect. Knowledge, unaccompanied
by understanding, has a low prognostic value, is soon forgotten, is
seldom up-to-date, and is tedious to teach and learn. Good attitudes and habits
are very important but we do not know how to teach them. They are not likely to
flourish, however, where emphasis is on knowledge, that is on rote learning.
There is less agreement on the choice of content, except for the growing emphasis
on treating science as a process of inquiry, what scientists do, rather than
merely as a body of permanent knowledge. There is an abundance of topics of
scientific importance. It is therefore possible, and highly desirable, to choose
those topics that are capable of arousing the pupil’s interest and increase his
ability to solve new problems, topics that are within his competence and conform
to the teacher’s interest and competence and the available physical facilities.
The content must be properly organized. A pupil will acquire knowledge and
understanding more easily and permanently if he sees each topic as a part of a
larger whole. Each large unit of instruction should continually draw on the previous
units; it is not enough just to state the connection at the beginning of the
new unit. There should be a coherent thread for each large unit: all of the unit
should be directed at solving just one problem; for example, why does heat flow
from hot to cold, or what keeps a satellite up?
The programme should have a plan for convincing the <strong>school</strong>, especially the
teachers, that understanding and ability to learn are the principal objectives of
science teaching and that the <strong>school</strong> can achieve these. A necessary step here is the
teachers’ reformulation of objectives even though the objectives may thereby be
somewhat distorted. Some teachers may prefer ‘problem solving’ to ‘understanding’,
for example. Such a rewording is legitimate provided the term refers to
genuinely new problems and not to exercises in formula substitutions or other
stereotypes.
Design ofthe teaching and testing. Every important behavioural objective must be
explicitly taught and its attainment tested. The main principle here is that we learn
by doing. Knowledge can be acquired by listening to the teacher or readinga book.
Understanding requires practice in handling new situations. Ability to learn re-
246 Evaluation and Examinations

quires practice in learning without the teacher’s aid, from a book or in a laboratory.
It is necessary, however, to teach the pupils how to attack new problems and
how to learn without aid. Learning theseintellectual skills takes longer thanacquiring
knowledge and requires special teaching techniques. An important pedagogical
device is to examine the pupils on each objective, for pupils work hard and
learn for tests.
To meet these requirements the programme should drastically reduce the usual
number of <strong>physics</strong> topics to be taught and to have a plan for reorienting the
teacher’s educational philosophy and for training him in the necessary pedagogical
and testing skills. Formal instruction in these skills is desirable but it is not
always practical and is never sufficient. The teacher’s own experimentation in
new methods is necessary. Educational experimentation is always a healthy thing.
The whole teaching atmosphere changes; some excitement and life appear on the
previously dull scene, and almost invariably both the teacher and the pupils profit.
The programme must therefore have a plan for encouraging and aiding local experimentation.
It is wise to point out, especially to the older teacher, that his pupils
do attain the principal objectives to some degree; that what is wanted is a shift in
emphasis and a more systematic approach.
Design of evaluation. The design of a programme of training must include detailed
plans for evaluating the programme at various stages of its develcpment. Evaluation
always implies rewards and punishments and can profoundly change the
teaching-learning atmosphere; it can aid a programme or it can ruin it. It is therefore
desirable to give each <strong>school</strong> considerable responsibility for evaluating its
own success. Moreover, it takes time to develop good evaluative instruments :
tests, questionnaires, interviews, inspections. It is therefore dangerous to postpone
evaluation plans till after the programme has started.
We can evaluate a programme by inspecting the teaching-learning processes or
by measuring their results. The inspection method is difficult because the science
of education is not sufficiently developed for judging accurately the appropriateness
of a teaching method under each set of local conditions. Moreover, an inspection
in the classroom is likely to disturb the very process that is to be observed.
The measurement method has the advantage that the most important result,
student learning, can be measured and described with fair accuracy. The method
suffers, however, from the presence of many elusive and uncontrollable factors
within the <strong>school</strong> and community that may affect learning. We conclude that both
the inspection and the measurement methods must be used.
At each stage of the programme, evaluation has a specific function. When the
programme is being introduced into a <strong>school</strong>, the aim of evaluation is to foresee
the major difficulties and to suggest modification. With the programme in action,
evaluation would be used primarily to help the <strong>school</strong> adjust itself to the programme
and to suggest further modifications of the programme. After the programme
has been in action for a few years, the primary function of evaluation is to
assess its impact on the <strong>school</strong> and community and to suggest the next step. Such
assessment should be repeated at proper intervals.
247 Evaluation of a Programme of Training

The design of an adaptableprogramme. A programme should be so flexible that it
could be readily redesigned to become feasible and acceptable to any participating
<strong>school</strong>. Changes may have to be made in the objectives, methods and evaluation.
Plans must exist for involving the <strong>school</strong> in the redesign of the programme
and for convincing it and the community that the objectives are worthy and
achievable, that the teaching methods are appropriate and not burdensome, and
that the evaluation wil be fair. The necessary rhetoric wil vary from <strong>school</strong> to
<strong>school</strong>.
The higher behavioural objectives of understanding and ability to learn should
be insisted upon, for a programme not aimed at these objectives is essentially
worthless. The flexibility would consist in allowing a <strong>school</strong> to gradually shift its
emphasis from knowledge to the higher objectives, and in encouraging teachers’
own formulation.
The content on the other hand should be flexible indeed. The textbook should
be so written that it would be easy to omit topics and chapters. The teachers’
manual should have suggestions for allowing pupils of different abilities to proceed
at different rates in the same class and for making the course manageable by
the least well prepared students. It would be irresponsible, for example, to teach
mathematical aspects of <strong>physics</strong>, except to students who know enough mathematics;
it would not be enough that they ‘had had’ a course in mathematics.
While the degree of permissiveness in the behavioural objectives should be
limited, there are two good reasons for allowing great flexibility in the teaching
method. First, very different methods can achieve the same objectives; and
second, teachers cannot be successfully coerced. If they do not trust a method,
they can go through all the prescribed steps, even with good will,without achieving
the desired results. The programme should have a plan for modifying the
initial teaching method in such a way that its difference from the method used at
the <strong>school</strong> is at first small. It should have plans for various kinds of educational
experimentation to fit the teachers’ interest and competence.
Flexibility in evaluative methods is necessary because of differences in pupils’
calibre and preparation, teachers’ competence, teaching method and experimentation.
This is especially true when the primary function of evaluation is creating a
better atmosphere, or otherwise improving the programme. Moreover, different
<strong>school</strong>s wil design different evaluative instruments. Even the final evaluation of
the programme wil require different instruments for different degrees of success.
The word flexibility, as used in this section, does not mean generality or vagueness.
Rather the programme should have several quite specific and detailed
variants. It is usually possible to group <strong>school</strong>s into a few categories : for example,
strong, medium and weak; large and small; urban and rural. If time permits, a
very specific programme should be written for each class of <strong>school</strong>s. Such a programme
should still have room for some flexibility. A very general programme
would be ineffective; a very specific programme that is the same for all <strong>school</strong>s
would be worse: it might be disastrous.
248 Evaluation and Examinations

17.1.2 Evaluation of a programme in action
The degree of success of a programme in a <strong>school</strong> can, and must, be prognosticated
on the basis of its design and the previous knowledge of the <strong>school</strong>. The
prognosis and the design wil change, however, as we observe the reaction of the
<strong>school</strong> at the time the programme is first introduced and when the programme is
fully operative. In the first place, the <strong>school</strong>’s reaction wil give us new knowledge.
In the second place, ifthe reaction becomes increasingly favourable, such progress
may justify a favourable prognosis.
In deciding whether to abandon or modify a programme it is essential to know
to what degree its failure is due to faults in the design, method of introduction or
execution. A record of the latter two processes must therefore be kept. The brief
sections below are not intended to tell how to introduce or execute a programme
but to point out the factors that wil be useful in evaluation.
Introducing theprogramme. The function of the introduction is to explain the programme
to the <strong>school</strong> and community and to create a favourable atmosphere. In
explaining the programme strong emphasis must be laid on behavioural objectives,
especially understanding and the ability to learn, for these wil be new concepts
to most <strong>school</strong>s. Teachers must be told what they mean, how to teach these
abilities, how to test for them and how to experiment with methods of teaching.
They should be asked to write down their ideas, to give examples of teaching
methods and tests. These papers should be discussed and the teachers should be
asked to try again. A record of the teachers’ responses should be kept.
To create an atmosphere receptive to the new programme is a formidable task
and wil require time and patience. In many communities it may be wise to make
the following pessimistic assumptions, without, however, showing open scepticism.
The community has doubts about the value of any education, even though it
knows that diplomas are useful. The teachers have little knowledge of <strong>physics</strong> or
modern teaching; they are afraid of, and hostile to, all change. The children dislike
and distrust almost everything about <strong>school</strong>.
The best atmosphere is that of interest and curiosity. But it requires a relaxation
of tension. The main <strong>source</strong>s of tension wil be fear of evaluation and of extra
work. Tension wil be relaxed if the <strong>school</strong> is convinced that the period of experimentation
will be genuinely just that; that the job of any outsiders wil be to help
and not to judge. Many routine chores may well be suspended or reduced till after
the experimentation. It is vital to be explicit and frank about evaluation. The
<strong>school</strong> should be told who wil evaluate, what and how he wil evaluate, and who
wil see the results. Teachers wil be reassured if during the experimental period
only they see the results, if the final evaluation wil be of the <strong>school</strong> and the programme,
and not of individual teachers, and if they participate in the design of the
evaluation.
249 Evaluation of a Programme of Training

Theprogramme in operation. The goal of evaluating the working of a programme
at a <strong>school</strong> is twofold. During the experimental period the goal is to help improve
its functioning. Later the goal is to furnish data for a prognosis: what changes will
make probable its success at that particular and similar <strong>school</strong>s. The aspects to be
evaluated are the same for the two periods; the difference lies in the use and confidentiality
of the results. In both periods we should note the indices of success of
the programme, its flexibility, and the factors peculiar to the <strong>school</strong> that aid or
hinder progress.
’The knowledge of what happens in the classroom is here essential. Is understanding
taught? It probably is if the teacher explains how new problems can be
attacked, allows the students to tackle other new problems, and criticizes their
efforts. Is the ability to learn, say from a book, taught? It probably is if the
teacher explains how to read and mark a passage, assigns new passages, and
criticizes the pupils’ responses. To make sure, the teacher must measure his pupils’
understanding and ability to learn and modify his teaching method if the test
results are unsatisfactory.
Few persons have the necessary tact and sensitivity to be able to observe a
teacher in action without disturbing him and the class. An alternative is to ask the
teacher to explain what he does, why he does it, and how he measures his success.
Even this indirect method is likely to succeed only if the teacher expects to be
helped, not censured.
It is during the experimental period that the flexibility of the programme shows
itself most clearly. Experimentation during this period is the order of the day.
Because of this and because the goal is to help, the <strong>school</strong> should be in control of
evaluation. Outside consultants will be most helpful if they are instructed to act as
such and not as judges. Especially they should avoid judging individual teachers.
If they must make reports they should submit them to criticism by the <strong>school</strong>. An
atmosphere of complete frankness must prevail. When the programme has acquired
certain stability, though it is still prudent and practical to let the <strong>school</strong> do
most of the evaluating, a degree of outside control to ensure the validity of the
evaluation becomes desirable.
17.1.3 Evaluation of a programme’s results
A valid evaluation of a programme requires an evaluation of the behaviour of the
pupils when they are adults. Such evaluation is difficult and costly, however.
Usually we have to limit ourselves to the academic setting. After a programme has
been in operation for a sufficiently long time (perhaps two to five years) its results
should be thoroughly evaluated. The following principles are here important.
(a) The evaluation should be prognostic. Wil the programme work in the
future? Wil it work if modified? If so, how should it be modified?
(b) The evaluation should be diagnostic, that is capable of tracing the programme’s
failures to the design, the introduction and maintenance, or the conditions that the
programme could not control. A diagnosis is clearly necessary for deciding on the
remedies.
250 Evaluation and Examinations

(c) It is necessary to evaluate not only the status of the programme but also the
progress made due to the programme. If students learn well, for example, but no
better than under the old programme, the new programme may have been a waste
of effort. A rise in learning, even to a modest level, on the other hand, justifies an
optimistic prognosis.
(d) All the important indices of success should be evaluated.
(e) The evaluative methods and instruments should be already familiar and in
principle acceptable to the <strong>school</strong>s involved.
Evaluation of pupil learning. It is difficult to estimate the pupil’s potential for
becoming a useful citizen. Therefore all possible <strong>source</strong>s of information should be
used : examinations, opinions of teachers, the pupil’s own opinion of himself. The
only information available is, of course, of the pupil’s past and present. But only
that part of that information is important which throws light on the pupil’s
future. Understanding, ability to learn and curiosity have this characteristic. So
do perseverance toward a pupil’s own goal and rebellion against stupidity and
ignorance. Evaluation of the pupil’s learning must be prognostic; it should not be
used as a reward or punishment for past behaviour. This fundamental requirement
is especially important in weighing teachers’ opinion of the pupil, for they
are likely to prefer nice, quiet children to more promising ones.
Examinations that test understanding and the ability to learn are probably the
most dependable prognostic measures of the pupil’s achievement. Here again,
variety is desirable. The examinations could be written, oral or performance. Useful
written examinations are questionnaires, essay tests and objective (multiplechoice)
tests. Oral examinations should include interviews as well as class recitations.
Performance includes the laboratory activities as well as anecdotal records
of the pupil’s behaviour in and out of the classroom.
The pupil’s self-evaluation is an excellent <strong>source</strong> of information. It is generally
quite trustworthy, especially if the information wil not be used for or against the
pupil. As with all opinion, it should be checked. If a pupil claims high (or low)
understanding ofa topic, the interviewer may well ask him a few questions on the
topic.
A teacher’s opinion is easier to use and validate if it consists of separate entries :
the pupil’s knowledge, understanding, ability to learn, punctuality, manners, etc.
A very high correlation between any of these indicates that the teacher observed
well only one or two characteristics, usually knowledge and manners.
Evaluation of teaching and testing. Similarly, high correlations between tests of
knowledge, understanding and the ability to learn usually mean that all the tests
measured mostly knowledge. Good learning is of course the best measure of
teaching, but usually the examinations are not good enough and teaching itself
must be looked at. Valid observation of classroom teaching is very difficult indeed
and should be supplemented by interviews. The interviewer can usually determine
the teacher’s competence in subject-matter, pedagogy and evaluation ; his understanding
of the programme’s goals; his familiarity with the pupils’ attitudes,
251 Evaluation of a Programme of Training

problems and home atmosphere; and, often, his attitude toward teaching in
general and in the programme in particular. The quality of the teacher’s tests is an
important index of his pedagogy.
What the pupils learn and how the teachers teach and test throw a good deal of
light on the <strong>school</strong>’s attitude toward the programme. Teachers’ experimentation
is another index, especially if it is voluntary. It is well, however, to put the question
of attitude directly and explicitly to the teachers, pupils, administrators and nonacademic
members of the community and ask for their criticism of the programme.
The evaluation of conditions over which the programme has little control is, of
course, essential injudging the intrinsic value of the programme. The literacy level
and attitude towards <strong>school</strong> in the pupil’s home may be as important as the pupil’s.
health and vigour; these wil depend on the sanitary and medical facilities, nutrition
and the imposed non-academic chores.
The pupil’s intellectual preparation for the programme, his native intelligence
and the academic level of other courses, is an important factor. The programme
may fail because the students lack technical preparation, for example in mathematics.
It may also fail because its intellectual demands are much higher or much
lower than those of other courses at the <strong>school</strong>.
179 Course evaluation
R. G. Munro
17.2.1 Why evaluate?
The measurement of the effects of <strong>school</strong>ing is a comparatively recent study and
its new prominence reflects a more general desire to evaluate the purposes and
outcomes of social institutions. Everywhere the tests of relevance and effectiveness
are being applied to established <strong>school</strong> courses and new curriculum products.
In <strong>physics</strong>, as in other disciplines, questioning is focused on the ability of <strong>school</strong>
work to achieve recognizable and valuable educational ends. In the past our
thinking about such ends has been severely limited; we taught <strong>physics</strong> so that
pupils would know about the discipline and pass examinations in it. We knew
nothing of the permanent effects of our teaching and, in fact, had no way of discussing
educational outcomes. As long as <strong>physics</strong> was regarded only as a body of
knowledge, teaching had but one purpose: to transmit information.
Fortunately, curriculum projects around the world have generatednew perspectives
on the discipline. Physics is now seen as a rich field of human inquiry possessing
its own unique structure and problem-solving processes. The new perspectives
have resulted in part from insights gained through advances in evaluative techniques.
Whileidentifying the testable we have sharpened our thinking about the
nature of <strong>physics</strong> itself.
The specific task of the course-evaluator in this era of educational questioning
is to find out whether or not a particular course leads to the continuous achievement
of its stated objectives. The evaluator accepts the aims of the coursedesigners,
measures growth towards their achievement and gives us the evidence
we need for judging the effectiveness of the course. Itis perhaps important to note
252 Evaluation and Examinations

that the course evaluator, as such, does not make judgements about the worthiness
of the aims themselves; this should be the province of curriculum planners and
those responsible for the overall balance of a <strong>school</strong> system.
17.2.2 Questions asked by evaluators
Too much evaluation is still concerned with measurements that do not tell us anything
about pupil growth. The question asked is: what is the achievement of the
pupils at the end of the course ?Evidence is often obtained from the results of public
examinations; ifthe pupils do as well or better thanothersusing an older course, the
new programme isjudged successful. Such an inference may be quite invalid. Not
only do we have no base line for comparing growth in the two groups (both would
need to be matched at the outset. at least in terms of achievement in <strong>physics</strong>), but
many variables remain unexamined as <strong>source</strong>s of rival hypotheses to account for
differences. For example it is usual for new courses to be introduced by enthusiasts
selected for their interest and teaching ability-predictably their pupils should do
well.Again the introduction of any new courses produces novelty effects (Hawthorne
effects) and any increase in attainment may well be attributed to the effects
of change itself.
Valid evaluation can only be made where gains in achievement are measured in
a typical classroom atmosphere and where strenuous efforts are made to take into
account the effects of novelty and teacher enthusiasm. Usually this can be
achieved where classes for evaluation are chosen at random and measurements
are made over a sufficiently long period to discount the effects of novelty. In these
circumstances the evaluator can afford to ask: does the course achieve what is
desired? The question can be answered if measurements are made before, during
and after the course has been used, and where the measurements are in terms of the
stated objectives. This latter restriction is often neglected in quite elaborate evaluations.
Courses which aim at developing, for example, an understanding ofconcepts
are evaluated in terms of public examinations which measure a narrower range of
purposes than those contemplated in the courses. Such evaluations are invalid in
terms of the purposes of the courses and tell us little about their true worth.
Perhaps one of the most misleading forms of evaluation is one which has very
general acceptance. The question asked is: do the teachers and pupils like the
course ? Often the question is answered in the affirmative by enthusiastic teachers,
administrators and curriculum promoters. Again, we learn nothing about course
effectiveness ; rather we are concerned with self-fulfiIling prophecies which result
in the new programme surviving in the curriculum irrespective of its merits.
It is disconcerting that those associated with the disciplines which have generated
the concepts of experiment, measurement and error should be unaware of
the importance of applying these concepts in evaluation. The question: does the
course achieve what is desired? should be regarded as comparable to the question :
does the iron bar expand when heated? To answer either question there is the
same need to design an experiment, make measurements and estimate errors. It is
in this sense that evaluation in education is a truly scientific enterprise.
253 Course Evaluation

17.2.3 The key: operational objectives
The form of stated objectives in any course is critical if effective evaluation is to be
carried out. Objectives which are vague or too general make measurement difficult.
It is now generally agreed that the operational statement of objectives is the
most useful. An objective becomes operational when teachers can understand
clearly what it means in terms of abilities and can follow and apply procedures for
measuring its achievement. The question that must be asked while formulating
such objectives is: what do pupils do to show that the objective is being achieved ?
For example, if we wish our pupils to develop an ability to analyse data we must
be prepared to state the pattern of behaviour which spells success in its achievement:
the abilities to distinguish the relevant from the irrelevant, detect trends
and avoid common errors in reasoning are part of such a pattern and immediately
guide us in what to look for in the work of the pupil.
As we enumerate the specific behaviours associated with an objective we begin
to communicate our view of its meaning to others and also begin to generate concensus
statements about it. Without this exercise objectives are left in a form
which encourages a wide range of interpretations and leads to confusion in the
minds of teachers. Interpretations of the meaning of understanding provide an
example of such confusion. Most contemporary courses claim to be promoting
understanding, yet examination questions suggest that the ability is interpreted so
widely as to be almost meaningless. For some examiners a knowledge of principles
is equated with understanding; for some the ability to apply principles in terms of
course content is accepted as evidence; and for others it is measured as the ability
to recognize principles in a set of multiple-choice alternatives. All these measures
may be telling an examiner about some aspect of understanding, but he can never
be sure that the pupil is not simply remembering the appropriate responses. Where
understanding is seen as the ability to apply principles in unfamiliar situations, we
have an operational statement which does not overlap other recognizable abilities.
The following list illustrates some objectives and behavioural criteria which can
help an evaluator recognize achievements in written and oral responses.
254 Evaluation and Examinations

Table 5 Some Objectives and Behavioural Criteria in Science
Skill objectives
Criteria for a marking schedule
The ability to :
memorize-information, symbols, Student recalls or recognizes appropriate
formulae, criteria, knowledge
methods, principles,
generalizations and
theories
apply knowledge
Student makes use of knowledge in familiar
and unfamiliar situations. (The latter ability
is often equated with understanding)
comprehend
Evidence in the answer that the meaning of
the question has been conveyed
analyse and interpret
Student judges relevancy of data, recognizes
trends andavoidscommon errorsin reasoning
extrapolate and predict
Student cautiously argues beyond the
presented data. (Graphically or verbally)
formulate-hypotheses
generalizations
explanations
devise experiments to test
hypotheses
Attitude objectives
Student forms an hypothesis, generalization
or explanation which can be tested
Student points up ways in which the
hypotheses can be tested
Student shows what evidence is needed
Student shows the procedures for collecting
evidence
The ability to be:
intellectually honest
open-minded
critically minded
accurate (numerically and
verbally)
Student gives his reasoning even though it
seems contrary to the accepted
Student willing to acknowledge ignorance
Student willing to abandon predetermined
ideas
Student accepts good evidence without
arguing
Student requests <strong>source</strong> of information
Student questions authority
Student questions validity of information
given
Student shows accuracy of thought when
reading question
Student is accurate in numerical work

If the objectives of a course are stated in this way evaluation becomes possible
because the abilities being measured can be readily detected in student responses.
17.2.4 The measurement of growth in <strong>physics</strong>
Measurements of achievement during, and at the end of, a course are valuable for
predicting success or failure in future studies, but they are insufficient for the
evaluator. A bench-mark is needed. Somehow he must attempt to put a valid and
reliable index on the entry behaviour of students so that growth can be measured
in terms of the abilities the students bring into the classroom.* Pre-tests are needed
and these should be administered before the course is introduced and should
measure the abilities the course claims to develop. At the outset some abilities will
be predictably more highly developed than others; generalized behaviours which
are shared by <strong>physics</strong> and other investigative studies, such as history, may be
already present, while abilities associated with the knowledge and principles of
<strong>physics</strong> may be absent. Studies have suggested that some students on entry to
<strong>physics</strong> courses have already achieved a high facility in analysing data and in
formulating hypotheses; it remains for <strong>physics</strong> programmes to harness and enhance
these abilities in the interests of inquiry in <strong>physics</strong>.
Once an index can be placed on a pupil’s entry behaviour, gains in ability can
be noted at intervals. However, it is usual for the evaluator to report the mean
gains of groups; errors may be too great to allow any useful significance to be
attached to the measurement of differences in individuals.
Measurements of growth are valid only where test instruments (pre-tests and
post-tests) are matched in certain ways. If a pre-test measures knowledge of one
topic and a post-test knowledge of another topic, there is no way of comparing the
two achievements. Comparison becomes possible if successive tests adequately
sample the full range of knowledge a pupil is expected to have attained at each
stage of a course. Gains in the ability to recall knowledge in the discipline are then
assessed. It is, however, important to distinguish such gains from scores in class
tests designed to measure immediate retention of content; the evaluator is more
interested in assessing recall of basic concepts and principles over the wholeperiod
of the course.
Where assessment of growth in higher mental skills is required (beyond recall),
questions in sequential evaluative tests should be matched in all respects apart
from content. Questions which permit evaluators to estimate, for example, the
development of the ability to formulate testable hypotheses should have the same
format, difficulty of language and sequence of subquestions.
Before a set of evaluative tests is used all questions should be tested for reliability.
Like two identical rulers, each question of a matched pair should measure
* A test is valid when it measures what an examiner sets out to measure. For example, if an examiner
claims to be measuring thinking skills and tests only for recall of information, his examination is invalid
in respect of its purpose. The reliability of a test is based on the consistency of its measurements. Like a
ruler a testshould give comparable results when the same thing is measured several times. A test has high
reliability if it gives similar results when set to different matched groups of children.
256 Evaluation and Examinations

the same abilities to the same extent. If this condition is not met. differences
between scores on the two questions wil have no meaning. Reliability is often
established by incorporating matched pairs of questions in a single trial paper
which is set prior to the:evaluative study, and to pupils outside the population
which is to take part. High correlation between scores in the paired questions is
accepted as evidence of test reliability. Several contemporary texts discuss alternative
methods of question-matching and of establishing test reliability.
17.2.5 Choice of measuring device
A comprehensive evaluation should measure achievement in u2l the stated objectives
of a course. Some evaluations stop short at intellectual measures and ignore
the claims of modern courses to develop laboratory skills, attitudes and interests
in science. If these latter are not taken into account, a bias is introduced into the
evaluation : investigation is confined to what the evaluator thinks are important
aims and the emphases of the course designers are placed on one side.
For the evaluator there are both direct and indirect methods of collecting
evidence of the attainment of objectives. Direct methods follow from behavioural
statements themselves. For example, the objective ‘skill in the interpretation of
data’ may be tested by giving the student new information and asking him to draw
inferences fromit. Similarly, interest can be measured directly by asking the pupil’s
opinions about the course. Attitudes are more difficult to assess directly, but the
evidence can be detected in the pupil’s responses to ordinary test questions. For
example, where a pupil is justifiably critical of the data given in a question we have
clear evidence of critical mindedness and can score it as a desirable attitude. It is
possible to structure questions in such a way that there are definite opportunities
for students to display the attitudes associated with the scientific temper. Marking
schedules can then be devised to score the attitudes separately from the main test
measure.
All direct methods of testing seem to be immediately valid with reference to the
stated objectives. Free-response questions can provide opportunities for students
to display clear evidence of mental abilities. interests and attitudes (free-response
interest information is, of course, obtained from questionnaires). The scoring of
such scripts or questionnaires is not easy, but provided markers work from carefully
defined criteria (such as those listed for mental skills and attitudes) a very
high degree of reliability can be established between independent markers. *
Objective tests and interest and attitude inventories are indirect measures.
Recall is tested by asking the pupils to recognize, the ability to analyse is tested by
asking them to select from given alternatives. Interests and attitudes are measured
by asking students to rank order or state a level of preference for (strongly agree,
agree, undecided, disagree, strongly disagree) interests or attitudes listed in a
* Marker reliability (as distinct from test reliability) is established by comparing the scores awarded by
different markers to the same set of scripts. When reliability is high, the marks given by the various
examiners will be very nearly the same. Marker reliability is usually low on traditional essay-type tests
and high in ‘objective tests’.
257 Course Evaluation

questionnaire or inventory. In the case of some attitude inventories, attitudes are
inferred from the students’ judgements about a variety of stated situations or
opinions. The advantages of all indirect measures are : firstly, they can be marked
easily and objectively, and results are therefore quickly available for summary and
analysis; and secondly, as ‘research’ tests their results can be readily subjected to
statistical treatments.
In spite of these advantages indirect measures (particularly of intellectual skills)
have only a limited function as evaluative instruments. Knowledge-recall and
some lower-order objectives can be measured by them, but at the moment it
would seem that structured free-response type questions are more appropriate for
measuring the kind of skills demanded in modern <strong>physics</strong> programmes. The
existing indirect measures of interests and attitudes are widely respected in evaluation,
but even here new forms of criterion-marked direct tests are thought to give
more valid results.
Perhaps the most important quality of free-response direct questions, apart
from their validity, is that they tap the ‘typical’ behaviour of students. Answers
are recorded in the thought forms of the students themselves, whereas responses
in indirect tests are always in terms of the language and thinking of the test-maker.
In a sense indirect questions tell us only about the ability of students to select from
the alternatives conceived in the examiner’s mind; they do not give us direct
insights into the thought processes of students.
Typical behaviour is associated with what a student does do as a result of the
course rather than what he can do. An evaluator needs evidence of typical behaviour
to draw valid inferences about the effects of a course. Where contrived or
counterfeit behaviour is elicited and measured, the evaluator can rarely disentangle
the effects of the course from those generated by other variables such as
competitive pressures. The atmosphere most helpful to valid testing is one in
which external pressures are at a minimum. There is less likelihood of contrived
response if a test is so designed that students can accept it as a challenge which, if
met, wil tell them something of worth about their abilities. The course evaluator
is often at an advantage here because he can insist that the scores wil not be
available to teachers or <strong>school</strong> authorities. Students are thus released from the
debilitating tensions so often associated with public examinations.
17.2.6 The plan of an evaluation
Factors which must be taken into account when planning a disciplined evaluation
include: hypotheses to be tested, the measures and population to be used, length
of the evaluation and the statistical procedures to be adopted.
Some evaluative hypotheses are discussed in the first section of the chapter;
many others can be formulated depending on the purpose of the investigation.
Whatever the purpose, hypotheses should be stated with clarity and simplicity.
To set out to show: ‘that this new course is better than its traditional equivalent’
is too vague an undertaking to be of value. On the other hand, the hypothesis :
‘that this course leads to achievement in the stated objectives’ is immediately of
258 Evaluation and Examinations

operational value, provided the stated objectives are behavioural or are easily so
stated.
The choice of evaluative instruments depends on the range and scope of the
investigation. In addition to measuring intellectual-. interest- and attitude-gains,
the evaluator may wish to sample the opinions of teachers and also determine the
effects of the course on teacher behaviour. Evidence of the teachers’ views of a
course can be collected through feedback sheets which provide teachers with opportunities
to report on difficulties encountered, strengths and weaknesses of the
course and their opinions about gains or losses made by their students. Such evidence
can supplement data obtained directly from students, but it must always be
treated with some caution because teachers’ assessments may be biased by their
expectations for the course.
Teachers’ opinions about the effects of the course on themselves are also
valuable. Modern courses are in large measure dependent for success on the goodwill
of teachers, and those who are antagonistic to the purposes of a course can do
unlimited damage to its development. It is important, therefore, for the evaluator
to obtain a representative picture of teacher dispositions. If the population for
evaluation has been chosen at random it is inevitable and desirable that some
feedback will be hostile; if it is not so it is likely that the sample is biased and the
evaluation therefore invalid. Course designers must accept the fact that if their
products are to prove of real value they must stand the test of being judged by a
representative sample of teachers rather than be lauded only by a carefully
selected band of enthusiasts.
Where a course purports to develop particular attitudes and ways of thinking in
students, it is useful to know if it is also affecting the classroom behaviour of
teachers. In a very real sense a course itself may contribute to the training of the
teachers it needs. Self-reports by teachers can help an investigator estimate such
effects.
The selection of an appropriate population for the purposes of evaluation is
sometimes difficult because not all the <strong>school</strong>s selected may be prepared or able to
take part. A random choice of <strong>school</strong>s from a representative area of a country is
the ideal for evaluation, but often the evaluator must content himself with something
less than this ideal. If comparison is required with another course, a second
random choice of <strong>school</strong>s may be necessary. However, where a course is being
measured in terms of its own objectives a comparison or control population is
rarely necessary. Only where two populations are working towards similar
objectives is comparison meaningful.
All evaluation should be considered as an on-going process, one which continues
as long as the course is used. Unhappily we are still a very long way from
accepting this concept in practice. Few evaluations are carried on long enough for
the evaluators to be quite sure that they are not simply measuring the effects of
novelty (Hawthorne effects). Probably at least five years of investigation. in as
many varied circumstances as possible, is needed before we can make statements
about a course with reasonable confidence. Certainly we must begin evaluation as
early as possible, preferably at the initial stages of a course’s development.
259 Course Evaluation

Measurements attempted at this stage can constantly inform revisions and
amendments. Eventually we must accept evaluation and revision as continuous
companion activities, for we are rapidly reaching the point where no course can
be accepted as an orthodoxy, even for a limited period, nor can we afford to
assume that evaluation is ever ‘complete’.
The statistical tools used to process measured results cannot be discussed here
in any detail. References are given for some re<strong>source</strong> <strong>books</strong>. At the moment these
are only guides in the educational field; there is a very real need for statistical
procedures to be adapted for experiment in education, particularly for the classroom
teacher.
The most helpful procedures are: correlation, analysis of variance and covariance
and chi-squared tests. Notwithstanding the difficulty of using some of
these devices, there are some useful principles that can be stated. Our main concern
when measuring changes in the behaviour of students is to establish the level
of confidence we can associate with our measures. Provided we have valid and
reliable test instruments, a mean gain-score of say 10 per cent may be either
encouragingly high or quite meaningless. Two factors largely determine the
degree of confidence : the number of students included in the sample and the distribution
ofthescores aboutthepre-test andpost-test means (standarddeviations).
In general, our statistical tests enable us to cite a figure which denotes the significance
of our results. Thus a 0.01 (1 per cent) confidence level placed upon a gainscore
tells us that there is only a 1 per cent probability (one chance in a hundred)
that the score could have arisen by accident. In other words, a measurement has
been made and the result is not determined by random factors. Other tests, such
as chi-squared tests, allow us to estimate, at a certain level of confidence, differences
between the scoring patterns of different groups. Such tests are useful
when we wish to test the hypothesis that there are different emphases in different
courses.
11.2.1 What is valid inference ?
When measurements are made and significance attached to them it remains for
the evaluator to draw his inferences. If he is to take into account <strong>source</strong>s of error
he will tend to be suitably tentative in his conclusions. A valid inference in this
very difficult field of educational evaluation is one that derives from valid and
reliable data and is qualified by open acknowledgement of the possible influence
of uncontrolled variables (such as novelty).
11.2.8 Replication and follow-up
Because of the many <strong>source</strong>s of error during an evaluation, it is essential that
replication is carried out in as many different circumstances as possible. A changing
balance of ‘truth’ wil inevitably occur during replication, but emerging
trends can be noted and used to inform further investigations. There is little doubt
that educational investigations cannot produce definitive answers. Replication
260 Evaluation and Examinations

can. however, help us to reach a point where the effects of a particular course can
be described with some accuracy. Whether it is a ‘good’ course or not is not
strictly a concern of the course evaluator; this should be the province of curriculum
designers and planners.
When effects have been described, follow-up is possible. All results should be
passed on to the people responsible for revision so that fresh insights can be acted
upon. A continuous interchange between evaluators and course developers should
be an ideal to be aimed at.
A final question which continues to disturb many educators: ‘Are we prepared
to abandon expensive courses and start again, if, after thorough investigation,
their effectiveness is shown to be insufficient to warrant the large changes required
for their implementation ?’ It would seem that the need for effective
courses is so great that the criteria of money spent and effort expended are insufficient
to justify the automatic acceptance of new curricula.
11.2.9 Appendix: Example of matchedpair of free-response questions
Two questions, one for use before and one after a first-year course in science.
Pre-test question. A kitchen is lit by an ordinary electric lamp which hangs a short
distance from the ceiling. The bulb gets hot when lit, and after a month of normal
use it is noticed that a dirty mark has appeared on the ceiling above the bulb.
The ceiling is cleaned and the bulb is replaced by a fluorescent tube at the same
distance below the ceiling. The tube remains cool when lit and the kitchen is now
brighter. Shadows of small objects have almost disappeared and there is no
marking of the ceiling a month later.
The observations are set out in this table.
Table 6
Dirt
Tempera-
Power Brightness marking Shadows ture
Ordinary electric lump high less Yes present high
Fluorescent tube low more no absent low
(a) How can you account for the dirty mark on the ceiling?
(b) What evidence is there that energy is being wasted?
(c) Why are there almost no shadows when the fluorescent tube is used?
(d) Do fluorescent tubes always give better lighting than ordinary lamps?
Post-test question. A loudspeaker in a <strong>school</strong> hall rests on a small table on the
stage. The loudspeaker has a blurred sound, and after three months of normal
use it is noticed that the speaker has begun to rattle.
261 Example of Matched Pair of Free-Response Questions

A new but otherwise similar speaker is then screwed firmly into the wall several
feet above the small table. The sound is now mellow and much clearer. Everyone
in a large audience can now hear and there is no rattle in the speaker three months
later.
The observations are set out in this table:
Table 7
Power to
Speaker
Speaker Clearness rattle Audibility Quality
Speaker on high poor con- first few rows blurred
table
siderable
Speaker on low good none whole of mellow
wall
audience
(a) How can you account for the rattling of the speaker?
(b) What evidence is there that energy is being wasted?
(c) Why is the audibility range so much greater with the speaker on the wall?
(d) Do tightly screwed down speakers always give better results than loosely
supported speakers ?
The marking. Responses to sections (a) and (c) are marked for the ability to
formulate testable hypotheses. Responses to section (b) are scored for ability to
analyse data and section (d) for ability to extrapolate (see behavioural criteria in
listing of objectives). Differences between the mean-scores of a group on the two
questions can then be used to determine growth (or otherwise) in the measured
abilities. The content of questions of this kind should be selected from topics
outside the prescribed course. In this way there is less chance that responses will
result from simple recall of information.
17.3 Examinations
At an OECD conference on science teaching, E. M. Rogers analysed and discussed
the many purposes for which examinations are set. He suggested that their
uses included the following:
(a) to measure pupils’ knowledge of facts, principles, definitions, laws, experimental
methods, etc;
(b) to measure pupils’ understanding of the work of the course;
(c) to show the teacher what the pupils have learnt;
(d) to show pupils what they have learnt;
(e) to provide pupils with landmarks in their study and checks on their progress ;
(f) to make comparisons among pupils, among teachers, or among <strong>school</strong>s;
262 Evaluation and Examinations

(8) to act as prognostic tests for directing pupils towards careers;
(h) to act as diagnostic tests, for placing pupils in fast or slow streams in <strong>school</strong>;
(i) as an incentive or spur, to encourage diligent study;
6) to encourage study by promoting competition among pupils;
(k) to certify a necessary level for employment in jobs after pupils leave <strong>school</strong>;
(1) to certify a general educational background for jobs;
(m) to act as a test of general intelligence for jobs;
(n) to qualify for university entrance, etc;
(0) to award scholarships, etc.
Professor Rogers continued by drawing attention to one more function of
examinations : to show the aims of a science-teaching programme. This is a most
important function that should not be overlooked by those involved in curriculum
reform.
There are those who feel that curriculum reform is not possible because ofthe
examination system in the country concerned. On the contrary, examinations can
become a useful vehicle to help achieve reform. The kind of questions set can help
to show both pupils and teachers what the course is trying to achieve.
If the aim is to introduce a new programme aiming at understanding and the
ability to apply principles to new situations, it is clear that there is no point in
pupils sitting old examination questions requiring factual recall. A new programme
requires new examinations.
A typical examination question in the past might have read as follows:
Define specific heat.
Describe how the specific heat of iron might be measured experimentally.
500 gm of iron is heated to 100 "C and put into 1000 gm of water at 10 "C.
Calculate the new temperature of the water if the specific heat of iron is 0.12 cal
per gm per "C.
What does such a question tell us about the <strong>physics</strong> course? What kind of
teaching does it encourage? The first part shows the pupils that the best way to
achieve success is to learn definitions by heart, whether or not the significance is
appreciated. The second part can be answered by giving an account of a standard
experident, complete no doubt with details about <strong>source</strong>s of error, without the
pupil having done the experiment himself or even having seen it demonstrated.
The third part is answered by substitution in a formula. The kind of teaching that
wil result is obvious: the teacher wil drill the pupils in memorizing definitions
and formulae, and he wil see that note<strong>books</strong> are filled with descriptions of standard
experiments. The teacher who does this well wil be rewarded by seeing his
pupils pass their exams and by certain criteria he wil consequently be considered
a 'good' teacher, even though his pupils may not have learnt much about science
in the process.
To illustrate this further, let us suppose that a class of pupils are studying
English. Part of the course may be devoted to language and part to English litera-
263 Examinations

ture. It is much easier to test grammar and it can be done with greater accuracy,
but ifthe examination is devoted exclusively to it the pupil wil very quickly come
to the conclusion that this is the part of the course that matters, however much the
teacher himself may feel that it is the literature that is the important part, giving as
it does insight into the thoughts of others. But a multiple-choice test, who wrote
what book or what poem, which character appears in which novel or which play,
can often be answered by the pupil who has a good memory without his appreciating
the book, the play or the poem, in fact without even having read them at all !
If the object of a <strong>physics</strong> course is to teach for understanding rather than rote
memory, the questions set in any examination must not militate against it. The
Nuffield Physics examiners, for example, have undertaken to quote all the necessary
formulae on the front of the examination paper; this at least makes it a pointless
exercise for pupils to memorize them.
As Professor Rogers expresses it :
If we are teaching for understanding of science, we should ask questions that inquire visibly
into the pupil’s knowledge: ask for reasoning, ask for the candidate to show his clear understanding,
ask him to describe scientific work. In short, we should give him problems that he
can answer if, but only if, he is following the course and achieving some of our aims.
Obviously, that ‘if, but only if’ is an ideal of examining that we can only strive towards . . .
The best we can do is to make examinations encourage success rather than prevent it.
17.3.1 Types of examination question
Many types of examination question are possible and all have been tried in many
parts of the world. Some countries put considerable reliance on oral testing; this
provides the best opportunity for communication between the candidate and the
examiner, but it has the disadvantage that it can tell against the nervous candidate
and there is the serious problem of coordinating standards between different
examiners. At the other extreme there are the advocates of objective tests that offer
a choice of ready-made answers. These can be marked by machine and eliminate
discrepancies between examiners. There is considerable enthusiasm in the United
States for multiple-choice examination papers and great skill can be acquired in
setting good questions, for which pre-testing is an important requirement. Of
course, multiple-choice questions can be devised which ask for creative thinking,
but it is much easier to produce questions asking for simple recall and the papers
often tend in that direction.
There are, however arguments against multiple-choice questions. Firstly, they
may leave traces of wrong knowledge in the memory of the candidate and thereby
do not help good teaching. Secondly, they prevent any opportunity for dialogue
between the candidate and the examiner and the candidate has no means of communicating
in his own words. Thirdly, an objective test may have a ‘best answer’
such as would be chosen by the average candidate whom one would wish to pass
in the examination, but there can often be a different ‘best answer’ which would
only be appreciated by a specially able candidate. With machine marking, this
candidate would get no credit, and an examination which penalizes the able pupil
264 Evaluation and Examinations

ecause he has no opportunity to communicate his thought-process is never
entirely satisfactory.
Between the two extremes of oral examinations and objective tests there is a
whole range of possible examinations : short-answer questions, long-answer
questions, essay questions, comprehension tests and practical examinations, all
of which have their advocates. There is a trend towards continuous assessment
rather than reliance on a national examination at the end of the course, and there
are likely to be interesting experiments in this direction in the next ten years.
There is also a tendency towards examinations which are internally set and
marked, but externally assessed. These tests can be particularly suitable for pupils
who are less academically able; they have the advantage that the vocabulary used
wil be that with which the pupils are familiar and thereby avoid the weakness of
some examinations where the difficulty for the pupil is often for him to decide
what the examiner wants.
17.3.2 Typical questions
A typical multiple-choice question is:
The graph below shows the path of a marble fired across the laboratory by a spring gun.
In answering the questions about this marble you may ignore the air resistance.
H
1. The speed of the marble as it leaves the gun is the same as its speed at
A G D K
B H E none of these
CJ
2. The horizontal component of the velocity of the marble after it leaves the gun is
A greatest at G D greatest at K
B greatest at H E the same at all points
C greatest at J
3. The momentum of the marble as it leaves the gun is the same as its momentum at
A G D K
B H E none of these
C J
4. The kinetic energy of the marble is a maximum at
A F
B G
D FandK
E GandJ
C H
265 Examinations
metres

The Nuffield 0-level external examination originally used two types of question.
First there is the short-answer paper with a space of a few lines for the
candidate to write his own answer on the question paper. These questions range
from factual items (‘simple recall ’) to make a comfortable beginning for anxious
csindidates, to questions requiring careful reasoning that draws on several pieces
of knowledge (‘expensive recall ’), and then to some that require imaginative
guessing for which there is not necessarily any right or wrong answer.
An example of a short-answer question is :
Nmv’
1. You have seen an equation for the pressure P of a gas: P = ~
3v
What do the other symbols stand for?
Vrepresents .............................................................
N represents ............................... ..
rn represents ......................................
urepresents ..............................................................
Explain why the factor f appears in the equation.
.. ............
........................................................................
........................... ............................
Putting in values of P, N, m and V gives a value of about 500 m s-l for air molecules
in an ordinary room. Do all the air molecules in this room move with this speed?
.......... ................... .....
........................................................................
........................................................................
The following are two examples of long-answer questions :
1. Jack and Jill
a
try to construct a new form of ripple-tank vibrator from laboratory
materials, not using an electric motor. Jack suggests the plan shown in Figure 18(b). He
proposes to connect a small, low-voltage mains (50 Hz) transformer at ‘<strong>source</strong> of a.c.’.
spring
glass ripple tank
<strong>source</strong> of a c
electromagnet
266 Evaluation and Examinations
Figure 18 (b)

3y
(a) Explain how this apparatus might work, i.e. produce the ripples desired.
(b) Why use a.c. rather than d.c.? What happens if d.c. is used?
(c) Actually the vibrator does not work even with ax., and Jill says she thinks the frequency
is wrong; they must use a frequency less than 50 Hz. They obtain a variablefrequency
power <strong>source</strong> and findthat there is one suitable frequency, less than 50 Hz which
produces powerful vibrations for only a small current. How do you explain this?
(d) They want to get a faster rate of vibration; suggest two ways in which this could be
done (they still have the variable frequency ax. generator).
(e) How could they demonstrate a ‘pulse’ of ripples?
(f, To show the ripples, they place a small filament lamp above the tank and white paper
on the floor beneath. They can see the bright and dark ripple pattern quite clearly: ‘Why
is it so clear?’ asks Jill. ‘Shadows’, says Jack. ‘Nonsense’ says Jill, ‘Clear water cannot
cast shadows; besides, some parts of the paper are actually brighter than when no ripples
are made in the tank.’ How do you explain the brightness of the ripple pattern on the paper?
A diagram wil assist your explanation.
2. A radioactive substance, labelled R, is set up in front of a G-M tube connected to a
scaler. The scaler is set counting at the same moment that a stopwatch is started. Every
time the second hand reaches a minute, a boy records the reading of the scaler without
stopping it counting. He tabulates the readings as shown below:
Time Scaler reading
0 0
1 6015
2 8026
3 9016
4 9401
5 9541
6 9802
I 9636
8 9613
(a) One of the readings is suspicious. Which one? What the ~ probably mean to
record?
(b) Having made this correction, work out from the readings what was the count rate in
each successive minute, giving your answers in number of counts per minute.
(c) What do these readings suggest is happening?
(d) Plot the count rates on a suitable graph and deduce a value for the half-life of the
radioactive substance R. (The mean of at least two values is required.)
(e) Jill says that a better result would be obtained if the readings were extended over a
further eight minutes and that the boy stopped too soon. Is this a good or a bad idea?
Give reasons.
(f) Jack knows that there are random fluctuations in radioactive experiments. He says a
better result would be obtained if more counts were taken and that it would be better to
count for five minute intervals, not one minute intervals. Give reasons why you think this is
a good or a bad idea.
(8) There is a slight increase in count rate during the eighth minute. Is this significant?
Give the reason for your answer.
267 Exa rn i nat ions

(h) Suggest any way in which you think the experiment might be improved.
The Nuffield Advanced Physics examination also incorporates a short-answer
paper and a long-answer paper. There is also a multiple-choice paper and a comprehension
paper, in which a piece of scientific writing is quoted at length and
questions on it are asked at the end to test pupils’ ability at comprehension.
Finally there is a practical examination in which a sequence of practical tests are
carried out by each candidate, testing their ability to handle apparatus, to make
observations and to draw intelligent conclusions.
268 Evaluation and Examinations

18 Teacher Education
It is they, the teachers now at work and now going through the training colleges, who are
shaping what Tanzania wil become much more than we who pass laws, make rules and
make speeches
President Nyerere
This edited chapter is based on contributions by S. Winston Cram. E. J. Wenham and
Joseph Elstgeest. Outlined first are some of the problems in the education of <strong>physics</strong>
teachers both in developing countries and in more advanced ones. The serious shortage of
<strong>physics</strong> teachers is alluded to. A discussion of what is required from the training of <strong>physics</strong>
teachers leads to detailed examination of pre-service and in-service training. The chapter
ends with a plea from Joseph Elstgeest for the kind of teacher-training he would liketo see.
18.1
Background to the problem : 1
There is no lack of curriculum-development schemes in the world. Curriculum-development
centres pour out new materials. Curriculum-development panels rejectand accept materials.
Curriculum developers blaze forth with new ideas. Curriculum-development publishers
circlekeenly around, gladly assisting in the spread of new teaching aids. But the implementation
of any new programme wil either fail or succeed with the teachers who wil have to use
it. There is a much greater need to change teachers than to change curricula.
There are thousands of serving teachers. often rusted in a routine, and handicapped by the
disease called ‘ syllabusitis ’. Too often, especially in past colonial systems. teachers were just
told what to tell their children. They happily or unhappily swung about with the tides of
changing syllabuses, and were never asked for their opinion, nor for their judgement. Even
the enlightened teacher who dared to experiment was told by the inspector: ‘This is all very
nice, and the children like it, but what about the examination?’ Most teachers acquired the
attitude of playing it safe, and pleasing the inspectorate by ‘keeping the standards ’. What
these standards reallywere was none of their business.
Next there are the young students in the teachers’ colleges. They are the product of the
very system they wil have to change. In many cases they have taken up teaching as a last
resort. The need for teachers in an expanding <strong>school</strong> system is often so great that the training
time is reduced to a minimum, the required qualifications are reduced to a minimum and
the rigorousness of the selection is reduced to a minimum. They have come through a
system of rote learning and do not share our dissatisfaction with the existing system. After
all,so they reason. this system was good enough to produce them; therefore it cannot be all
that bad. But they forget to ask themselves about the 90 per cent that were left behind; what
good did it do to them?
269 Background to the Problem : 1

The students have come through a system of rote learning in order to be successful in the
exams. It is difficult for them to change their attitude. Their conservatism, together with a
certain degree of intellectual inertia, ‘if you learn what you are told to learn, you will be busy
enough’, catches them in a vicious circle. They (rote) learn the modern principles of
education, but teach the way they were taught. This vicious circle must be broken.
So writes Joseph Elstgeest of Morogoro Teachers’ College in Tanzania, and his
solution to the problem lies in better teacher education. Of course he appreciates
that the causes lie deep in the old system of education:
From a broad primary base the ‘best’ were picked out by a selective examination and further
trained towards some profession. This system did produce many good and reliable servants
for the public and the private sector, and no doubt fitted the contemporary situation. But its
persistance is totally unfit for, and indeed detrimental to, the progressive development of a
free nation as a whole. A dangerous illusion was created: education is a monetary investment,
leading by its nature to well-paid jobs and the bright lights. It was a kind of state
lottery: those who were ‘successful’ in this system drifted away and became estranged from
their society, while the ‘failures’ returned frustrated and defeated. The ‘successes’ were able
to wield a vaguely defined power vested in some higher authority, while the ‘failures’ were
faced with poverty and drudgery in poor rural areas with no way of leaving this situation and
no way of changing it for their kind of education had not taught them how to do this. All of
a sudden there was an ‘unemployment’ problem, in the face of vast tracts of unproductive
land because it was thought that ‘education’ must lead to paid employment: serving for
money. Certainly there was health education and agriculture and science in the <strong>school</strong>
curriculum, but that was learned for the exam; the better you answer the questions on agriculture,
the better your chances of never having anything to do with it!
Joseph Elstgeest’s solution lies in changing the science education so that
all citizens are educated to make intelligent decisions, based on an understanding of their
environment, carried along by a constantly inquiring mind, and reinforced by the ability to
identify and solve problems arising from the needs within this environment. The ability to
think independently and to reach conclusions only on the strength of reliable evidence will
then help the people to share their intellectual re<strong>source</strong>s in communal planning where
decisions are made. These decisions will depend on evidence presented, interpretations
shared, and the amount of understanding acquired.
This kind of science education is a long way from rote memory work and the
only hope of changing this is through teacher education, both pre-service and
in-service.
A similar view comes from many directions. For example, after twenty years of
working in developing countries on curriculum reform in science and on teacher
training, T. L. Green stresses the need for seeing science education against the
social background. ‘ Science education must be seen as an agent of social change,
its aims and outcomes must be described and defined in social terms and the
curriculum work associated with it must be a continuing social evaluation.’
Reluctance to accept social changes is often found right across the social
spectrum, from the top of the administration down to the class teacher, who in his
relationship with the pupil maintains this position of authority. Professor Green
writes :
270 Teacher Education

The teacher in general is often not only conservative in his nature, but is under strong social
pressure to remain so ; moreover he has had little in the way of socid training. He sees his
role as that of teaching science and is concerned with what he was trained to think of as
important: covering the syllabus and getting pupils through examinations. No one placed
much stress on the idea that he is to be engaged in changing society. Such an idea is too
remote because his task and his training have been set in the dimensions of immediacy.
I stress the need to give to science teachers an understanding of their social functions
which will result in theirusing theirknowledge of science to achieve social change. The task
is not easy; what is to be sought is not merely an understanding of social functions, but the
acceptance of a new role as an agent of change. We need teachers who wil produce innovators,
who will produce critics,who will stir interest, challenge effort and instil in the
minds of youth that divine discontent which sets off the search for the new and the better.
However carefully prepared, however well intentioned new programmes for
the teaching of science may be, they will stand or fall on the teachers. Teacher
education is therefore an essential consideration.
18.2 Background to the problem: 2
It must not be suggested that the above problems are typical only of developing
countries. The same problems, of rote memory work and teachers teaching as
they themselves were taught, beset the developed countries.
The following survey comes from S. Winston Cram of Kansas State Teachers’
College, and shows something of the position there:
At the turn of the twentieth century, <strong>physics</strong> was considered one of fiveor six basic courses
that should be taken in the senior year of high <strong>school</strong> if the student was to be considered
eligiblefor college entrance. Although the total high-<strong>school</strong> enrolment in the early 1900s did
not exceed 20 per cent of the youth who were at the age for secondary education, nearly all
the seniors took a course in <strong>physics</strong>. The subsequent trend to enlarge the number of youth
who attend high <strong>school</strong> (now nearly 85 per cent of the age group) and the trend towards a
liberalization of the courses offered have caused the percentage of students in the senior high
<strong>school</strong> to decrease markedly. The necessity to reduce the mathematics content in the high<strong>school</strong>
curriculum to enable the larger proportion of students to enrol has also led toa reduction
in the proportion doing <strong>physics</strong>. There was some difficulty for the populace to realize
that a high-<strong>school</strong> diploma did not mean the same thing for everyone! To physicists it was
accepted either that <strong>physics</strong> was not for everyone or that more than one type of <strong>physics</strong>
course must be available forhigh-<strong>school</strong> students.
In the 1950s, with the advent of the sputnik era, the unpopularity of <strong>physics</strong> courses led
physicists to realizethat the textbook material available for high-<strong>school</strong> <strong>physics</strong> was neither
accurate nor attractive. The outcome was the new approach to <strong>physics</strong> teaching in secondary
<strong>school</strong>s, known as the PS SC (Physical Science Study Committee) scheme. It accepted that a
fewer number of topics needed to be studied, accompanied by a new approach to teaching,
laboratory centered, where the spirit of inquiry prevailed and the discovery approach was
dominant. A teacher’s guidebook was included as part of the programme, a new innovation
in which the teacher was told exactly how to conduct the course, what to do in the laboratory,
how to work the problems and was given the answers to some of the questions which
were often beyond the comprehension of certain teachers.
So innovative was the PS S C <strong>physics</strong> course that it set off a chain reaction of new course
development in allthe science areas from kindergarten through the whole <strong>school</strong> programme.
271 Background to the Problem: 2

Unfortunately it has not as yet carried through into the college system in the USA, and
that is where some of the current problems lie. Courses such as C H E M, C B A, B S C S,
IPS and E SCP, to mention only a few, have grown out of the original idea and have shared
much of the original PSSC philosophy. Even the more recently developed Harvard Project
Physics (now called Project Physics) shares much of the instructional philosophy of the
PSSC programme, though it also includes a great deal of the humanities approach as well.
The grave aspect of both the PSSC and the Project Physics course lies in the oft made
statement ‘Oh yes, either course can be a very effective programme for a wide variety of
high-<strong>school</strong> students if the teacher has a satisfactory subject-matter comprehension and is
versatile in his manner of presentation.’ Here lies the real crux of the problem of <strong>physics</strong>
teaching in the high <strong>school</strong>s today.
The implication is obviously that our high-<strong>school</strong> teachers are too often not well prepared
for their task.
State and national statisticsin the United States show that 85 per cent of the high-<strong>school</strong>
<strong>physics</strong> teachers in the nation’s <strong>school</strong> systems teach at most two lessons of <strong>physics</strong> a day.
This means that for this 85 per cent <strong>physics</strong> is of secondary importance; their primary concern
is for some other area of instruction, often biology where the mathematical requirement
is less than for <strong>physics</strong>. The dilemma exists that we have two fine new <strong>physics</strong> programmes
ready for use when well prepared teachers are available to teach them, but in the
vast majority of the classrooms such teachers are not available.
Summer institutes, six to eight weeks in duration, and seventeen in-service institutes
attempt to overcome the dilemma. To use the new programmes the teacher needs the opportunity
to become thoroughly aware of the philosophy of instruction almost as much as
he does of the subject matter. The statisticsclearly show that the teachers who have used the
PSSC course material and then dropped it are in the vast majority of instances those
teachers who did not have preparation in the philosophy of the instructional process of the
PSSC course and were using the new materials but at the same time the old approach of
‘next time, next chapter’, and are trying to use the laboratory work to verify classroom
learnings. Those teachers who have developed the process idea and are using the laboratory
as a discovery approach in the true spirit of enquiry are generally still using PS S C.
The lack of penetration of the new innovations into college level has its effect on the preservice
training of secondary teachers. The new teacher tends to teach as he was taught.
Since this new teacher saw very little of the ‘spirit of enquiry’ as he sat in h~s college science
class, he is not ina position to incorporate it in his classroom. Colleges, in general, have been
very slow to change theirinstructional procedure. The American college professor is prone
to spend a summer in India helping the Indian teacher to learn about ‘ laboratory centered’
methods, and then he returns to the United States and continues his established lecture
procedure, using his prepared lecture notes to teach by telling.
In the United States there is also the problem of numbers. In a survey of 41 colleges and
universities, selected because of their interest in the preparation of secondary-<strong>school</strong> <strong>physics</strong>
teachers, the student enrolment varied from 2400 to 35000. The median enrolment was
9500 and the median number of persons in their senior year preparing to be <strong>physics</strong> teachers
was two! The number of prospective <strong>physics</strong> teachers showed no correlation with the size of
the institution; it depended almost invariably upon the amount of interest and concern
actively expressed by one or more <strong>physics</strong> staff members at their institution. The future of
<strong>physics</strong> in secondary <strong>school</strong>s in the US A is in a doubtful state : the hope lies in the increasing
concern shown by the <strong>physics</strong> staff in colleges and universities.
272 Teacher Education

Figures in the United Kingdom are also alarming. Those pupils in the academic
streams of secondary <strong>school</strong>s likely to go on to higher education start specialization
at the age of sixteen when they enter the ‘sixth form’ and begin their advanced-level
(A-level) work. The proportion of those in the first year of their
A-level work studying arts subjects shows a steady increase, as does the proportion
of those doing a mixed arts/science course, but there is an alarming fall both
in the overall numbers (despite the increasing numbers in the sixth form) and in
the percentage of those studying the sciences, as Table 8 and the graph below
(Figure 19) show.
If one were to do something as unscientific as to extrapolate onwards the line
representing the science graph it would reach zero in 1984. a significant year for
readers of George Orwell! Of course this wil not happen and it would be nice to
think that the slight change in 1968 and 1969 owes something to the influence of
the new English science-teaching programmes. But there are also other alarming
figures, for example the decrease that has been occurring in the percentage of
first-degree graduates going into teaching. A similar story could be told of many
Western European countries.
Table 8 Number of Pupils in First-Year Sixth Form
I963
1964
1965
1966
1967
I968
I969
Science grotip Non-science group Mivrd c/riiiip Total
Number Number :/, Number ‘:, numbers
~~-
35880 39.6 45263 504 9430
10.4 90573
40091 37.5 54530 51.0
12404
11.6 107025
38363 35.3 55929 51.5 14275 13.1 108567
37489 33.8 58263 52.5 15260
13.7 111012
36483 31.4 61298 52.8 18369 15.8 116150
36709 30.1 64396 52.8 20851 17.1 121956
38092 30.0 65367 51.4 23618 18.6 127077
273 Background to the Problem: 2

proportion of first-year sixth form on each type of course
%
Figure 19

18.3 Education of <strong>physics</strong> teachers
For many children integrated science studies are likely to be more appropriate
than a study of <strong>physics</strong> as a separate subject. Integrated courses are certainly appropriate
to the primary <strong>school</strong>s and also to comprehensive secondary <strong>school</strong>s.
Physics as a separate subject is likely to be taught in selective secondary <strong>school</strong>s to
the bright pupils and to some older pupils in comprehensive <strong>school</strong>s. This situation
arises from the sophistication of <strong>physics</strong> (as evidenced by its use of mathematical
language and ideas) which precludes it as a study for all. Yet many of the
fundamental concepts of <strong>physics</strong> are essential tools for all and consequently
<strong>physics</strong> must be an essential component of all integrated science courses.
Specialist <strong>physics</strong> teaching is likely to be offered to pupils of reasonable ability
only and, indeed, the offer is likely to be accepted only by such pupils. It follows
that, while some <strong>physics</strong> teachers wil combine their work with that of teaching
within an integrated science course, many are destined to work as specialists with
brighter children only. The specialist <strong>physics</strong> teacher must expect to teach
children who are intellectually more able than he is himself. Faced with this situation
he must clearly develop an understanding of the concepts of <strong>physics</strong> of the
highest possible order. This is not enough however; it must be matched by a corresponding
understanding of the problems which his pupils wil encounter as they
struggle with this fascinating but difficult subject.
Here then are two aspects of the education of a <strong>physics</strong> teacher which demand
careful consideration. On the one hand he must have a knowledge and an understanding
of the subject which goes far beyond that of his pupils: on the other hand
he needs a knowledge and understanding of suitable educational techniques and
effective teaching procedures with all that this implies in understanding children.
The <strong>physics</strong> teacher who ignores the basic findings of such investigators as Piaget
does so at his peril. The education of a <strong>physics</strong> teacher must provide for both
aspects of his work, and different countries adopt different practices in the attempt
to do this. At one extreme there is the system in which the prospective teacher
takes a research-orientated undergraduate programme in a university <strong>physics</strong>
department and then goes straight into teaching. Some countries insist on a
period (often a year) of teacher training in a specialized institution, for example a
university department of education, after the first degree has been taken. An
alternative route (usually provided in a college of education or teachers' college)
provides for the concurrent study of <strong>physics</strong> and of education in a course of two,
three or even four years duration.
18.3.1 Education in<strong>physics</strong>
The needs of the <strong>physics</strong> teacher differ significantly from those of the future professional
physicist. Whereas the latter must have a thorough preparation in
mathematics and an intensive study of <strong>physics</strong> with frequent excursions to the
frontiers of the subject, the former needs a wide background in the sciences, some
appreciation of the history and philosophy of his subject and a second teaching
subject. His concern wil be with his ability to explain <strong>physics</strong> in words rather than
275 Education of Physics Teachers

in mathematical symbols; and he must be at least as interested in people as he is in
<strong>physics</strong>. The task of the future <strong>physics</strong> teacher is not only to teach his pupils some
<strong>physics</strong>, but to convey to them some feeling for the nature of scientific enterprise.
He must never forget, as so many teachers often do, that only a tiny minority of
his pupils wil continue with the study of <strong>physics</strong> after leaving his classes; for the
majority his courses may provide their only contact with <strong>physics</strong>. He must remember
this constantly and his concern must be with the education of the general
public through <strong>physics</strong> and not just with the pre-training of the future research
physicist.
Only a university-degree structure which offers a considerable measure of
flexibility is capable of meeting such diverse needs a$ those of the <strong>physics</strong> teacher
and the career physicist. Fortunately experience with such flexible courses is
available in many American (Commission on College Physics, 1968) and
Scottish universities and, more recently, in the new structures adopted by some
English universities, including Cambridge and London (Jones, 1969).
It is worth noting the interesting technique used in many universities in the
USSR where students spend some time actually teaching in <strong>school</strong>s as part of
their degree course in <strong>physics</strong>; this makes them aware of the possibilities in
teaching.
Colleges of education (or teachers’ colleges) are usually able to plan their
<strong>physics</strong> courses with the needs of the future teacher in mind. Their problem is the
converse of that facing the university <strong>physics</strong> department. Where the latter may
lose touch with the needs of the young teacher, the former can easily lose touch
with <strong>physics</strong> itself. It would seem wise, therefore, to concentrate college courses
for future specialist teachers of <strong>physics</strong> in a few colleges which could employ
several physipists and provide them with the expensive facilities necessary to support
the courses. At a time when there is a declining interest among students in
<strong>physics</strong> and <strong>physics</strong> teaching this would be both economically and academically
desirable.
18.4 Pre-service training
However he gains his understanding of <strong>physics</strong>, the intending teacher must also
undertake suitable studies in the fields of education and methodology. These
studies must provide him with the opportunity to practise his skills within the
<strong>school</strong> situation and to observe competent teachers with differing teaching styles.
A period of teaching practice provides the young teacher with the opportunity to
develop his own teaching style and wil always be regarded as of the highest importance
by the intending teachers themselves. If it is to be as valuable as they
themselves believe it to be, then it must be the joint concern of the <strong>physics</strong>education
tutor and of the staff of the <strong>school</strong>. This demands close cooperation.
It is a truism that a teacher candidate is primarily concerned with his subject.
When he thinks about teaching that subject he is more concerned with his need
for essentially practical guidance about the subject than he is about the children
he wil teach. He wil expect to receive ‘tips for teachers’ which wil allow him to
survive the first impact of the practice-teaching period. He wil be concerned about
276 Teacher Education

the selection of lesson material and about managing the laboratory situation, and
he will expect to receive some guidance on how he might develop the practical
skills of class management. He is likely to have as his model his own teacher from
his <strong>school</strong> days or even his <strong>physics</strong> professor. At this stage he wil be singularly
inept at matching his material to the needs of his classes.
It is desirable, therefore, that the period between the commencement of the
course of training and the first full teaching practice should be devoted to discussions
of the essentially practical factors which impinge on the work of the teacher
of <strong>physics</strong>. Now is the time to concentrate on the methodology of the subject. As
the experience of the classroom and <strong>school</strong> develops, the student wil come to
realize the importance of the study of children and of education. It soon becomes
clear that there must be general aims and specific objectives in the <strong>school</strong> lesson
and the <strong>school</strong> course; there must be aims for education itself. It wil be evident
that there is a corpus of knowledge about the psychology of children which has a
direct impact on the day-to-day work of the teacher, and that a study of educational
sociology has much of value to offer. The young teacher can then see the
need to study those factors in society, in the pupil, in his own presentation and in
himself, with consequent effects on his teaching, his <strong>school</strong> and his pupils.
It would seem wise, therefore, to plan a teacher-training course so that it starts
with the severely practical, using material which is obviously relevant to the classroom
situation as seen by the young teacher who has not yet taught; that this
period should last until a major teaching-practice period and that, subsequently,
the course should turn to a consideration of those wider issues which are usually
embraced in courses on educational psychology, the aims of education and educational
sociology.
The courses in methodology shouldgive major attention to methods of teaching
the conceptually difficult topics in the subject, and to the planning of lessons and
courses in relation to the aims and the objectives of the programme which is being
undertaken. This work, which concerns <strong>physics</strong>, must needs be done in a laboratory
which is well equipped to good <strong>school</strong> (not university) standards. The equipment
should include not only a wide selection of the sort of equipment which the
young teacher is likely to meet in the <strong>school</strong>s, but also a good selection of the aids
which educational technology now offers the teacher. This might include a slide
projector, an overhead projector, a 16 mm sound projector, a loop projector,
good duplicating facilities (including the ability to make good quality overhead
projector transparencies) and, perhaps, a videotape recorder. There should also
be access to a laboratory workshop. Whether re<strong>source</strong>s are limited or not, it is
desirable that the young teacher should be introduced to the simple techniques of
handling tools and materials. He should, at the very least, feel competent to read a
drawing and he should have sufficient confidence in his own powers to use the
basic tools of the laboratory workshop. These tools need not be complex; all that
is required is an introduction to the use of the basic hand tools of the wood- and
the metal-worker. Developing his expertise in this art is almost certainly best left
to later in-service courses.
These technical considerations must not, however, be allowed to upset the
277 Pre-Service Training

alance of the course to the detriment of other skills which the teacher must
develop. These will include those skills which are concerned with the design of
courses themselves and with the evaluation of the work being done. In this context
the young teacher must learn to state the objectives of his work (Bloom, 1965,
and Nedelsky, 1956), whether it be a single lesson or the development of a major
area, in precisely defined terms. This demands that he should consider techniques
appropriate to the evaluation of the progress of the work, whether at the individual
or at the class level. Consideration of such evaluations will cause modifications to
the original programme and even to the individual lesson. In countries where
external examinations are important to the pupils he must be introduced to the
techniques used in such examinations (Pidgeon and Yates, 1969). The teachingpractice
period or periods will bring to the forefront of the student’s mind the
need to develop those skills in the field of human relationships which affect the
classroom situation. Whatever guidance can be given in the art of providing
pupils with motivation, and in the ability to discern the differences between individuals,
to understand their responses and to react quickly to the feedback
presented to the teacher by the class will be invaluable.
All this presents the teacher trainer with a formidable task, a task which is not
made any easier by the necessarily low level of background knowledge and experience
which his students will possess. After working for some years at the very
real difficulties presented by the subject of <strong>physics</strong>, the young teacher may find the
relatively low level of the studies undertaken in the field of education irksome.
This is an added reason for basing these studies as firmly as possible on the reality
of the <strong>school</strong> situation. Where such studies are undertaken concurrently with the
work in the field of <strong>physics</strong> itself, then the task of the teacher trainer is so much
easier. In this style of training the opportunity to spread the teaching-practice
periods throughout the longer course is invaluable. One can ensure at this stage
that the student sees several <strong>school</strong>s of different types; and that the lessons learned
in one period of practice are carried forward to the next; and due attention can be
paid to the importance of improvement from practice to practice. But whichever
method of initial training is adopted, the training can never be more than introductory.
The vitally important period lies ahead and especially in the first year of
teaching. That is the time when the young teacher needs all the help which can be
given him by his colleagues. In a large <strong>school</strong> with a wise and experienced staff he
will receive this guidance and, perhaps even more important, the encouragement
which will allow him to retain his ideals. But too often the young <strong>physics</strong> teacher
is the only representative of the discipline on the staff. This is a lonely position and
a dangerous one. This is where some of the means of liaison between teachers and
with university departments can play an important role. These are discussed in
the next section in in-service training. Meetings with others can be a tremendous
help to the young teacher.
18.5 In-service training
It is now widely recognized that every teacher, whatever subject he teaches,
should maintain a continuous process of professional growth. This applies with
278 Teacher Education

accentuated emphasis to the teacher of science, firstly because science is expanding
at such an accelerated pace that it is easier than in most other subjects for the
science teacher to become out of date; and secondly because knowledge of child
psychology has introduced new methods and techniques of science teaching. It is
therefore necessary to help the science teacher to become familiar with these
methods and techniques and their effective use (Commonwealth Education
Liaison Committee, 1964).
After a few years teaching the <strong>physics</strong> teacher invariably feels the need for
refreshment. This need exists at two levels; at the first level it is concerned with the
subject itself. Whilst it must be recognized that it is not possible to retain that
contact with the frontiers which seems so desirable, some attempt must be made
to keep abreast of the significant developments within <strong>physics</strong>. In this attempt
journals such as ScientiJic American and New Scientist are of great help. But
an occasional course held under the auspices of a university department can
do a great deal to boost the morale of the <strong>physics</strong> teacher. It is important that such
courses should be mounted with the greatest of care, especially with regard to the
relevance of what is said and done, and that the needs of the participants as
teachers should not be forgotten. Experiments should be of a fundamental nature ;
lectures and seminars should be given by men who appreciate the status (<strong>physics</strong>wise)
of their audience. A group of <strong>physics</strong> teachers is not a group of young postdoctoral
fellows and the material presented to them must be carefully chosen with
due regard to the twin criteria of significance and relevance.
There is, however, a second level at which in-service training should be provided
for teachers. This concerns developments in the teaching of <strong>physics</strong>. It is
unlikely that the world wil again see such a spate of new courses in <strong>physics</strong> as
have been published in the last decade. Rather one hopes that progress wil be
made by local developments within a relatively small field. Dissemination of
knowledge of such developments cannot rely solely on published papers. There
must be opportunities for teachers to meet together to consider the development
in depth, to work with the appropriate equipment and to consider all the implications
as well as the subject content involved. This requires a series of short courses
of perhaps a week or ten days duration, and preferably these should be residential.
The major advantage of the residential course is the opportunity offered for
informal contact between the teachers taking part and their tutors.
There is a need for men to run such courses, to act as tutors and to help with
future curriculum-development work. They must be people who wil command
the respect of the teachers attending the courses. For such future leaders, a longer
course than the usual short-vacation course is desirable. Experience in the United
Kingdom with residential courses of ten weeks duration has shown the value of
this.
Small groups of experienced <strong>physics</strong> teachers were brought together in a college
of education for a period of ten weeks and provided with every opportunity to
develop their own interests in a situation in which they had access to well equipped
laboratories and to highly experienced tutorial staff. It was customary to start the
course with a careful examination of some aspect of the Nuffield 0-level <strong>physics</strong>
279 In-service Training

course. During this period the teachers displayed their own interests and, after a
week or ten days, began to plan their own programmes for the remainder of the
course. Consequently no two courses were ever alike. The strain on the tutorial
staff was recognized to be considerable, even though the formal timetable commitment
was deliberately kept as low as five formal sessions and two informal sessions
in each week, supported by at least two laboratory sessions with staff
members present. For highly motivated students such as these a timetable becomes
largely an irrelevance and the tutorial problem is to persuade them not to
do so much work that they become too tired to be receptive to new ideas. Although
the numbers attending the courses have been small, the success can be
judged in terms of the work subsequently done by those who attended; this includes
the organizing of short in-service courses and the undertaking of work with
curriculum development projects. A valuable <strong>source</strong> of experience for these
particular courses has been the number of teachers who have attended from
countries other than the United Kingdom.
It must not be forgotten what advantages are to be gained by strong, active
associations of science teachers. The value of teachers meeting together to exchange
ideas and to discuss difficulties cannot be overestimated.
In large centres of population, it may be possible for the department of <strong>physics</strong>
in the local university to sponsor <strong>physics</strong>-teachers centres (Clegg, 1969) where, at
monthly or more frequent meetings, <strong>physics</strong> teachers at all levels can meet together
in a way that is partly social and partly professional. The closer the association
between physicists in industry and universities and physicists teaching in
secondary <strong>school</strong>s the better. One must not underrate the effect on morale
brought about by treating the secondary-<strong>school</strong> teacher as a physicist, not merely
as a teacher; and this reflects to the good of education.
In many countries the growth of in-service work has been largely haphazard
and has often been derived from the impetus provided by the publication of a new
curriculum project. It is time that this development should be placed upon a
firmer footing. At a time of rapid change in the subject and in the teaching of the
subject it should be recognized that <strong>physics</strong> teachers must themselves constantly
undergo training. Teacher education does not end with the recognition of the
recipient as a qualified teacher. It continues throughout life. In-service training
must be seen to be as important a part of the life of the teacher as initial training.
18.6 Postscript: What kind of teacher training?
A final postscript to this important topic may be left to Joseph Elstgeest of
Tanzania.
The teachers’ college must keep ahead of the changing patterns in educational thinking, and
gear its programmes towards it. The main task of the college is not to provide the trainees
with a bag ofteaching tricks, nor with so called ‘higher academic background knowledge’ as
if it were a glorified Secondary <strong>school</strong>, but to train them in, and to help them accept, a
complete change of attitude towards their profession, towards children, towards the society
in and for which they work, and thus towards education.
280 Teacher Education

In the field of new science education, the acquisition of a new attitude is a slow process,
sometimes painful, sometimes rough, but always interesting to watch and rewarding in the
end. It is essential initiallyto introduce the students to a number of activities based on the
ordinary local environment, to get them involved in some basic experiences of problemsolving
activities of the type we envisage for the children they wil teach. This often necessitates
some shock treatment and a little brain-washing. It usually meets with quite some
resistance.
When encouraged to investigate various soil samples for the amount of animal life
present some of my students objected: ‘We Africans are not interested in these small
creatures.’ Another time the students were to do work on moments using a wood stand and a
stripofpegboard. Such apparatus can be remarkably sensitive and quite accurate. Of course
they were all able to recall the law of moments, but they had the greatest difficultywith the
simple problems to be solved with these pegboard balances. This was painful, and they
violently objected to working with these home-made balances; they said: ‘We are used to
proper analytical laboratory balances.’ Yet it is absolutely necessary that they go through
thisstage. It mainly serves toinitiatethe students into the true nature of scientificand mathematical
processes: to develop and reinforce scientificand mathematical concepts; and to
illustrate how this is transferred to a <strong>school</strong> situation. The initial resistance wears off soon
enough when the surprises come, when they find satisfaction and thus gain in confidence.
Constant reference ismade to pupils in the <strong>school</strong>s and the basic goals and principles of an
effective science education. This is often done in discussions which arise from the activities,
from difficulties encountered and from successes achieved. Whenever possible pupils are
brought in. A small group of students may work with a small group of pupils. They may try
out a new idea, introduce a new piece of local apparatus, or conduct an activity they have
talked about and experimented with. The value of these micro-teaching situations lies in the
opportunity to watch real children and their response to the problem-solving situations
created forthem, and at the same time to help the students recognize the merits or demerits of
the materials used.
Once the students gain in confidence, they are encouraged to open up new areas of study.
There is never a lack of interesting areas of scientificinvestigation. Some areas may have a
greater emphasis on scientificabilities,whereas others may have a greater mathematical bias.
In all cases there is every reason to encourage the students to follow their own interest
wherever it leads them. Two students taking up the challenge of making a simple pendulum
swing in a perfect figure of eight spent two days of trying and trying again, slowly collecting
clues, and finally succeeding. Open-endedness is an essential characteristic of this kind of
approach. The awareness that personal interest is the main indicator of the direction of
study is an important part of theirtraining.
There is no better way of training science teachers than by actually involving them in
exploring and trying out new ideas, experimenting themselves, and considering and evaluating
the pedagogical possibilitiesof their own ideas and apparatus. The complete absence of
pressure from pre-determined academic standards makes the students free, flexible and confident.
This may help them to become less dependent on written <strong>source</strong>-materials once they
start teaching. They become more alert in encouraging pupils’ interests and so avoid a
situation of so-called rote discovery by the pupils.
<strong>Teaching</strong> practice, where they are in full charge of a class of real pupils, gives them the
opportunity to convince themselves of whatever they think of this approach, or to convert
themselves to whatever we think of it. To many this is a real revelation. The pupils are never
a problem: they take to new science with glee and enthusiasm as soon as they realize that the
strait-jacket of ‘academic’ instruction is taken off.
281 Postscript: What Kind of Teacher Training?

Naturally, not every student teacher is equally successful and some do manage to make a
mess of things. But we do have fine examples of classes bursting with activity, and teachers
exclaiming that the pupils know more than they do, because they are so keen in observing
and finding out, and are allowed time to do so. The student teachers really benefit from these
enjoyably noisy classes where pupils are learning instead of being taught. The pupils in the
end are the best teacher trainers, and this is the most convincing part ofthe student’s course.
This account comes from a developing country, but perhaps many a developed
country has much to learn from it.
282 Teacher Education

Appendixes

A Case Histories
This section of the volume is concerned with a number of projects which have been
produced in various parts of the world. This particular appendix describes various case
histories of development work incorporating details of some of the problems encountered
during implementation. It is hoped that these experiences will be of assistance to those
embarking on new programmes.
A. 1 . East African secondary-<strong>school</strong> science project
V. J. Long mid G. vun Praagh
Until recently science teaching in East African secondary <strong>school</strong>s has been along
traditional lines taught largely by expatriate teachers and directed towards the
Cambridge Overseas School Certificate. During the past three or four years the
spirit of reform in the teaching of science has spread to many developing countries
and East Africa has been among the first to start a curriculum development project
in secondary science.
It was well known that great changes had been taking place in the United
Kingdom, changes accelerated by the activities of the Nuffield science-teaching
project. Ideas from the Nuffield Project became known through their <strong>books</strong> and
through teacher vacation courses assisted by the British Council and the British
Ministry of Overseas Development. However, it is difficult for teachers in developing
countries to put these ideas into practice in the existing framework of the
examination syllabuses, text<strong>books</strong> and so on. A full curriculum development project
was needed in which new courses, <strong>books</strong>, examinations and teacher training
all evolve together. It was realized that there must be clearly defined objectives,
and tests to see whether these objectives are being achieved. New <strong>books</strong> for both
pupils and teachers, and suitable in-service courses for teachers were all necessary.
C E D 0 (Centre for Educational Development Overseas) exists to help developing
countries to carry out such projects and the East African secondary science project
is a good example of what can develop with such help.
The project itself grew out of courses in Nuffield Science held in Tanzania,
Uganda and Kenya during 1966-7. A request came to CEDO from the three
ministries of education to convene a conference in Nairobi in March 1968.
Representatives from the three ministries, from the education departments of the
universities and from <strong>school</strong>s in the three countries there agreed to work towards
285 East African Secondary-School Science Project

the production of new secondary science courses in biology, chemistry and <strong>physics</strong>.
This would be a joint venture and it was hoped that the product would be useful
not only in the East African countries but also possibly in other newly developing
countries.
The courses would be based on modern principles of science teaching, aimed
at giving the pupils a real understanding of what science is about and how a
scientist tackles his problems. This cannot be done by mere book learning. If
children are to understand a phenomenon, they must come face to face with it.
This implies a good deal of practical work in the study of science. The teacher is
more of a guide than an instructor and there is more emphasis on pupil activity
and less on rote learning. The Nairobi conference decided that the new courses
would be built up by modifying the Nuffield courses and trying them out in East
African <strong>school</strong>s. The modification would take account of the children’s background,
their future careers, the natural re<strong>source</strong>s of the countries, the teachers and
the money available for secondary-<strong>school</strong> science.
This process of trying out the materials and modifying them in the light of feedback
from the trials is vital to the production of suitable courses. By rewriting the
material in the light of the feedback (which may be in the form of written reports
by the teachers in the trial <strong>school</strong>s or may be reported at conferences) a process of
continuous evaluation is going on. It is essential that the material should be
shown to be teachable by real teachers to real pupils in real <strong>school</strong>s.
The kind of modification to the Nuffield courses needed varies from subject to
subject. Chemistry is perhaps the easiest to adapt and requires only a slight change
in emphasis towards local <strong>source</strong>s of materials (for example, copper in Zambia),
and the inclusion of the chemistry of some local industries such as the manufacture
of cement. Nuffield biology needs less adaptation than might be thought at first
sight, but of course it is necessary to substitute local plants and animals and their
habitats for those used in the British course. Physics is the subject needing most
modification. The apparatus supplied by the Nuffield <strong>physics</strong> course is too expensive
for use in secondary <strong>school</strong>s in general. A lot can be done to reduce the
cost by local production of simple apparatus, but, while adhering to the principle
that real understanding comes to the pupil only when he is directly confronted
with the phenomena, it may be necessary in a few cases to reduce the quantity of
apparatus provided, and this means that children may have to work in groups
larger than ideal or assist the teacher to operate the experiments. Nuffield <strong>physics</strong>
is a structured course with definite objectives, namely, the understanding of the
very small, the structure of matter and of the very big, the structure of the
universe. These are not necessarily the most suitable objectives for a <strong>physics</strong> course
in East African <strong>school</strong>s, where engineering topics such as the properties and use of
various materials of construction, or the technicalities of the means of communication,
for example, may be more important at the present time.
Trials in chemistry began first in Tanzania in 1967 and were extended later to
the other countries and the other subjects. All subjects are now (1970) in their
second year of trials and in addition the third year of chemistry is being tried out
in Tanzania. Altogether about 120 <strong>school</strong>s and 20000 children are involved.
286 Case Histories

It is, of course, essential that these children should not suffer by being experimented
upon; in consequence the East African Examination Council wil set special
papers for them in the School Certificate, beginning with Chemistry in 1970.
The aim of the project is to produce a well-tried course, embodied in teachers’
guides, pupils’ <strong>books</strong>, experiment guides and <strong>books</strong> of questions, as a new examination
syllabus. The writing of the pupils’ <strong>books</strong> and teachers’ guides is being
undertaken by a number of individual teachers in the three countries. The science
panels of the ministries in the three countries meet periodically to coordinate the
work, the overall coordination of which has been the responsibility of CEDO.
When asked by the country to do so, CEDO, with the help of the British
Council, has arranged for science teachers from the United Kingdom to visit East
Africa and run courses to assist in coordinating the work going on in the three
countries, and to help with some of the writing. CEDO also received copies of
most of the draft material for comment and has been able to supply finance to help
with a variety of costs in addition to those implicit above, for example in printing
some of the draft material, in obtaining some of the apparatus, in paying for
secretarial and other assistance, and in supporting efforts to have simple apparatus
manufactured locally.
The three ministries have given the trials their full support and are taking increasing
responsibility for the project. A great deal remains to be done in order to
bring it to fruition, but as some helpers in the field leave so others come and it will
be the responsibility of the ministries and of C E D 0 to help to provide continuity
so that the project can be carried through to the production of <strong>books</strong> and the
training of teachers. It is encouraging to find that the establishments responsible
for teacher training in the three countries are already introducing their students to
the approach to science teaching embodied in S SP and to that part of its content
which is already available.
A project of this sort must have a product or the effort put into it is as water into
the sand. It is hoped that by 1972 (or 1973 in the case of <strong>physics</strong>) the East African
project will have produced all the materials necessary for teaching the new course.
In chemistry there wil also be some film loops and background readers ; loops
have already been made on diamond mining, cement manufacture and sugar
refining, and booklets have been written on ‘ Salt in East Africa’, ‘ Sugar ’, ‘Fermentation
and Distillation’ and so on. Those working on the <strong>physics</strong> are successfully
producing apparatus at very considerably lower costs than is possible in the
United Kingdom. The biologists are developing courses suitable to East Africa
and are making use of the Unesco Regional Biology-<strong>Teaching</strong> Project set up
three years ago in West Africa, among other <strong>source</strong>s of ideas.
This year (1970), halfway through this four-year project, the three ministries of
education in East Africa convened a second conference, this time in Kampala.
Coordination between the ministries is provided by the Secretary of the East
African Examinations Council. The object of the conference was to survey what
has been written and otherwise accomplished so far and to plan ahead to the conclusion
of the project. This may be marked by a third conference in the third
country, Tanzania.
287 East African Secondary-School Science Project

Once <strong>books</strong> and other aids are produced, <strong>school</strong> science in East Africa wil have
a ‘new look’: more interesting, more lively and, we hope, more relevant to the
needs of the pupils. The project is the first of its kind and no doubt other countries
embarking on the development of their <strong>school</strong> science wil have much to learn
from the East African experience.
A. 1.1 The <strong>physics</strong> course
Under the influence of dull examinations, the purpose of <strong>physics</strong> has become for
some people seriously misunderstood : as a subject for exercising mathematics, as
a package of disconnected facts, formulae and laws, or as a process of measuring
uninteresting constants with greater and greater accuracy.
There is no reason why <strong>physics</strong> in <strong>school</strong> cannot be presented as the exciting
subject it is, giving understanding of a wealth of things which happen in nature,
with curious crosslinks and astonishing powers of making life much easier or
much harder. The responsibility for bringing in the change rests on us all: the
designers of courses, the teachers who guide their classes through them and the
examiners who test real grasp at the end.
The problem of languages. Although the new entrants to secondary <strong>school</strong>s have
shown competence in written English, they find difficulty in exchanging ideas
orally. Serious discussion in the class is often more lively in the vernacular tongue.
Not only are the technical words in English difficult, and words and phrases based
on analogies current in Europe but not in Africa, but the stresses used by the new
teacher may hinder comprehension.
We have taken pains to use the simplest language in the pupils’ sheets. But in
some areas the first few weeks of Year 1 are spent less on teaching <strong>physics</strong> than on
establishing contacts. The exhibition, which begins the course, and the essential
talk about it can help. It is remarkable in how short a time most of the pupils
adjust themselves.
In Tanzania the solution is easier because good Swahili is known by most of the
pupils. In that country we expect these writings to be translated into Swahili.
The older pupils in the secondary <strong>school</strong>. The position is complicated by the wide
range of ages in the secondary forms. We expect that in time these ranges wil be
reduced, so we have attempted to write more for younger than for older pupils.
This could lead to resistance among the older members, who may fear they are
wasting time. Impatient for knowledge, they may prefer to learn of other
scientists’ discoveries without attempting any of their own. To deal sympathetically
with this we need to restate our intent.
Science makes headway by a mixture of speculation and experiment. If only established
knowledge is given, at second hand, the nature of the scientist’s struggle cannot be understood,
yet this is perhaps the bestcontribution the science course can make to the student’s
adjustment to the new world he will live in. He has to flavour the experience of discovering,
through difficulties,something unexpected; not by reading a book or watching a cinema
film,but for himself. Then, because we cannot wait for him to acquire all knowledge at first
288 Case Histories

hand. we add demonstrations, but even they are not to be accepted passively. The teacher
and classprobe the possibilitiestogether and suggest ways of checking them. By such means
the pupil can grasp <strong>physics</strong>, so as to be able to apply it successfully in later years.
If the class is taken into confidence at the outset and the policy explained, we
think pupils will accept the design. Even so, much depends on the teacher, who
moves round as the class goes to work. asking challenging questions, keeping
minds alert and occupied. We know this involves him in a lot of hard work, but
we suggest that at no time is he engaged more fruitfully.
Manualsfor teachers. There wil be a shortage of highly skilled teachers in East
Africa for many years. Some specialist graduate teachers with experience are very
successful, but we have not written the manuals for them. W e have aimed at the
beginner, who can be less sure of how to teach material at this level than at the
higher level of his college studies.
We have included advice on ways of introducing topics. on getting apparatus to
work, on making do with local re<strong>source</strong>s when equipment fails to arrive in time,
on how to keep a whole class mentally active and on some common errors. Much
of this wil be wearisome reading to the older teacher. We suggest a single reading
for him, to find the odd ideas that may be new, and more than one reading for the
newcomer to <strong>physics</strong> teaching. It can be a better investment of time to give an
hour to planning before lessons than two hours to correcting afterwards.
Worksheets. Opinions differ on the value of these. If worksheets give an exact
statement of what has to be done, and details of the argument to be followed, they
are an invitation to the student to follow the instructions like a recipe book, and
not bother about planning his experiment. On the other hand, to lay the apparatus
before him, with no advice, would be too difficult for him. Our worksheets are
intended to give only enough for a pupil to start. They can be issued with the
apparatus, or the teacher may decide that he can get the class fully at work
without them.
We have to cope with large classes, all engaged in individual practical work and
proceeding at different speeds. Sometimes, because apparatus is limited, different
experiments are being done by different groups in the class. In such circumstances
we find worksheets can help, but the teacher has to decide when to use them.
Problems. By contrast, no defence has to be made for problems, for homework,
for classwork, perhaps for examinations, to discover how far the class is really
understanding the <strong>physics</strong>. Our problems have been selected with the African
pupil in mind, though we have not hesitated to take good questions from any
<strong>source</strong>. We do not suggest that every pupil should try all the questions.
They demand more than effort of memory. In assessing the answers a teacher
looks for evidence of hard thinking rather than remembering, even when the
remembering is ‘right ’.
The upparatus required. Science teaching, especially of <strong>physics</strong>, has been hampered
here by lack of funds and by long delays in delivery of apparatus from Europe.
Yet because practical work is vital, enough equipment is needed for all the class to
be engaged. The problem is being studied seriously in all three countries.
289 East African Secondary-School Science Project

(a) In selecting material for a four-year course we have avoided topics demanding
expensive equipment, wherever they could be omitted without injury to the whole
course.
(b) We are experimenting with holding stocks of necessary items, expensive but
only required in the course for a short time each year, at convenient centres from
which they can be borrowed. Institutes of education, and some training colleges,
make good centres, for they have technicians to maintain the apparatus in good
order. A secondary <strong>school</strong> with a strong advanced course in science, Forms V and
VI, is another possible place. Other arrangements are being tried where the
demand is greatest.
(c) For items which at present have to be purchased overseas not only Europe and
America are used. Good electrical meters at modest prices can be obtained in bulk
from Japan.
(d) Some items are being constructed in the three countries. Production has been
set up in a university college by students during vacation, at a teachers’ college by
skilled technicians, in the technical department of a boys’ <strong>school</strong> and by private
firms. This local contribution can grow steadily as it is given support from the
ministries.
(e) There are always teachers who will make apparatus for their classes, often
with pupils’ help as a self-reliance exercise. Designs for some home-made items
are included in the appendixes to the manuals. But a teacher should not be expected
to undertake mass production of equipment; he can only do so by neglecting
what is more important.
The course has been worked out in East Africa by teams composed mainly of
practising <strong>physics</strong> teachers. It is intended that the work of the first two years
should form a basic, integrated course that is complete in itself.
The working parties studied what is being done in other countries and were
strongly influenced by the work of the Nuffield teams in the United Kingdom.
Acknowledgement of the help thus gained is gladly made. It should be noted,
however, that the endpoints for the African course are different and therefore the
route followed is by no means the same.
It would be inappropriate here to give full details of the course, as this is still in
the trial stage, but some indication of time allocations proposed might be helpful.
The estimates of timing were tentative, intended only as a rough guide. We assumed
a <strong>school</strong> year of thirty-six weeks and three periods of <strong>physics</strong> in each week
throughout the course. Some Uganda <strong>school</strong>s were allowed only two periods a
week in Years 1 and 2. They found it necessary to modify the course, omitting
the microbalance and postponing the lever and energy changes from Year 1 and
reducing the time on pressure. In Year 2 it was necessary to make serious cuts in
the time given to wave phenomena and to postpone radiation to Year 3.
The allocations for Years 3 and 4 are speculative; we shall know how acaurate
they were when trials have been completed. We expect that Year 1 and 2 are too
full, but we hope that Year 3 will be a time for catching up.
290 Case Histories

Table 9
Year I
Exhibition
Changes of state
Measuring, weighing
Gases
Micro balance
Thickness
Guessing, timing
Introduction to forces
Lever and seesaw
Springs
Year 2
Forces and turning effects
Force, energy, machines
Friction
Surface tension
Length of oil molecule
Measuring heat
Specific heat
Expansion
Change of state
Year 3
Movement
Force and motion
Forms of energy
Waves
Spectra
Electromagnetic spectrum
Theories of radiation
Electrostatics
Electrolysis and ions
Periods
6
4
4
2
(4)
2
2
2
(4)
4
2
8
4
2
4
2
2
8
2
8
10
14
12
4
6
2
2
6
10
Electrons in wires, etc.
Mechanical properties of materials 10
Notch effect and strengthening 10
Year 4
Fluid flow 6
Newton’s third law 3
Stretching wire
Elastic solids
Pressure in gases
Pressure in liquids
Particulate nature
States of matter
Model oPa gas
Electrical circuits
Conductors and currents
Energy changes
Conduction and convection
Radiation
Wave phenomena
Reflection of sound
Ray optics
Electrostatics
Electromagnetism
Simple theory
Periods
2
2
8
2
4
2
4
10
4
(4)
3
(5)
(12)
1
14
2
12
2
If this timetable could be kept, there
would be time to transfer fluid flow
from Year 4 to Year 3.

Table 9 - continued
Satellites
Momentum
Electrical energy and EMF
Alternating current
CurrentIPD relation
Electrical power
Ionization and radioactivity
Pictures and atoms 6
Atomic energy
Importance of energy to society
2
(4)
8
6
4
9
12
6
4
8
We assume that one-third of Year 4
may be reserved for revision. If
necessary some items of this year
could be omitted, e.g. momentum, or
reduced in time, e.g. atomic energy.
Even though some of the later topics
can only be described and discussed,
they are important and can be taken
quite seriously at this stage.
A. 1.2
,4.2
A.2.1
Postscript
How wil the <strong>physics</strong> of this project develop?
As the <strong>school</strong> trials are completed, working drafts (called seconddrafts) of at
least the first three years are being prepared for the panels and the three ministries.
A further series of papers is being written, as teaching guides, on the work of
Year 4. Candidates from the accepted <strong>school</strong>s wil be entered for the special papers
set by the East African Examinations Council.
The following steps can then be expected:
(a) The three ministries wil come to conclusions on the suitability of the materials
for their <strong>school</strong>s. It seems reasonable that they wil find parts acceptable but ask
for other parts to be modified or revised. Further writing wil be done, more and
more by African members of the panels.
(b) The three countries, under the coordinating influence of the Examinations
Council, wil contrive that their courses, if not identical, are close enough for a
single examination to be set for East Africa. The Council wil set School Certificate
level papers initially as an alternative to existing <strong>physics</strong> papers, and <strong>school</strong>s
wil be able to choose which course to follow.
(c) As the course takes shape, publishing of all materials wil be undertaken.
(d) Alongside this, but probably at a rather slower pace, a new course in physical
science, with its own examination papers, wil be prepared.
Integrated and coordinated science courses in New South Wales
Harry Messel
Introduction
After some fifty years of very little change in the secondary <strong>school</strong> system and in
the curriculum, in 1961 the government of New South Wales instituted a number
of far-reaching reforms with considerable ramifications for the teaching of science.
292
Case Histories

The Science Foundation’s project thus arose from the reorganization of secondary
education in New South Wales under the Wyndham scheme, named after
H. S. Wyndham, the former chief planner of this state’s modern pattern of secondary
education. The book project was a unique effort to endeavour to solve the
many problems arising from the implementation of new science courses which
were part of the Wyndham scheme, itself a most significant departure from the
previous system of secondary education.
The new science courses were so radically different from the traditional courses
previously studied that when the new syllabuses were prepared there were no text<strong>books</strong>
in existence which could adequately and specifically cover them or give the
necessary guidance to teachers now compelled to prepare lessons in unfamiliar
fields. Furthermore the whole outlook and philosophy towards the teaching of
this new science was different from anything the teachers had faced before.
Professor Messel recognized the problem, proposed the creation of the much
needed text<strong>books</strong> and led a specially chosen group of scientists, teachers, lecturers
and administrators to prepare them. He invited the Science Foundation
for Physics, of which he was founder and Director. to become the publisher of the
textbook series.
New South Wales followed and extended considerably the trend set by the
United States wherein the writing of modem scientific <strong>school</strong> text<strong>books</strong> was no
longer left as a task for a few prominent scientists or teachers but was undertaken
as a national cooperative venture between the nation’s leading scientists and
teachers and the government’s own educationalists. The very magnitude and
scope of scientific knowledge in the many fields which must be mastered today
demanded nothing less.
Since writing began late in 1961 the Australian group has produced seven <strong>books</strong>
in varying formats and in revised editions. It should be noted at the outset that a
significant condition determined the shape of the project. This was: the new
syllabuses, prepared for and authorized by the statutory authorities, preceded the
text<strong>books</strong>. The authors thus wrote to interpret a radically new but existing syllabus.
To this extent the project again differed from other science-curriculum
development efforts overseas which sometimes involved the concurrent production
of syllabus, texts and re<strong>source</strong> materials.
It is not the policy in New South Wales officially to present text<strong>books</strong> for study
or to base public examinations on them. Teachers are thus free to choose their
own text<strong>books</strong> although they must cover the prescribed course. The manner in
which they do this is again a matter for individual decision, governed only by the
stated aims of the syllabus. It should be noted however that the writing groups
associated with the textbook project included many members of the syllabus committees,
so guaranteeing a correct interpretation of each syllabus. The same
remark applies to the examination committees.
A.2.2 General
In the Wyndham scheme of education the New South Wales secondary-<strong>school</strong>s
course usually begins at the age of twelve and continues to the age of eighteen. It is
293 Integrated and Coordinated Science Courses in New South Wales

split into two : a period of four junior years (12-16, known as Stage 1) followed by
a further period of two senior years (16-18, known as Stage 2). At the end of the
first four-year period students sit for the School Certificate examination, an
examination set by the State. About 25 per cent of those students completing the
four-year course go on to the final two years, at the end of which they sit for the
Higher School Certificate. Passes in certain prescribed subjects at this level automatically
give the student matriculation for entrance into the universities.
The first four years of secondary education, Stage 1, are intended to provide the
skills and attitudes needed by all adolescents, whatever their ultimate careers or
objectives may be, if they are to be properly prepared for life as citizens in the
modern world. Education for citizenship rather than the preparation of an elite
for tertiary studies was the professed and dominant aim of these earlier years of
secondary <strong>school</strong>ing. The School Certificate examination at the end of Stage 1
was seen as the termination of this general educative process and educational
authorities have resolutely resisted any tendencies for the demands of higher
education, in the later years, to dominate or mould the education of adolescents
during the first four years of secondary <strong>school</strong>ing.
A number of basic premises are written into the educational philosophy of the
new system and reflected in the curricula and <strong>school</strong> organization. Among the
more significant of these are the parity of esteem between subjects studied, the
nurturing of talent in whatever field it is revealed, the progressive selection of subjects
for deeper study, the rejection of earlier streaming into rigid courses and the
provision of an essential ‘common core’ of fields of study related to the general
needs of adolescents and which are very broad in scope.
Every existing syllabus was withdrawn and new syllabuses were written to
reflect the new thinking and in particular to achieve greater relevance to modern
society. Each Stage 1 four-year syllabus provided for four levels of study, Modified,
Ordinary, Credit and Advanced with possibilities for transfer between levels.
Perhaps of greatest interest to science educationalists were the decisions to
make science, some 750 periods of it, a compulsory subject for every student
during the first four years and the rejection of specialized science studies in favour
of an integrated study of the major sciences.
During the fifth and sixth years (the senior years of Stage 2) of secondary education
the emphasis tends toward preparation for tertiary studies, but not exclusively
as these two years are also seen as a continuation of the educative process of
the earlier years. Provision is made for worthwhile courses to meet the needs of
students not intending to proceed to tertiary studies but wishing to extend and
enrich their secondary education. It is hoped that an increasing number of such
students will adopt this practice. All existing senior syllabuses were also withdrawn
and new syllabuses were written. Most of these syllabuses were radical departures
from the previous orthodox syllabuses.
In the field of science the most significant decision at the senior level was again
to reject the study of separate sciences in favour of a coordinated study of at least
three sciences. The content of these courses followed on, and interlocked naturally
with, those of the first four years. The syllabuses were again prepared to cater for
294 Case Histories

students with differing aptitudes and interests. There are four levels of courses :
First level, Second level short, Second level full and Third level, with time allocations
varying from eleven to six periods per week. These Stage 2 courses are at
present being reassessed and amended.
The Third-level science course is an integrated study of the four major sciences
(<strong>physics</strong>. chemistry, biology and geology), to some extent an extension of the first
four-year science courses, while the First-level course provides for considerable
specialization in one of the three sciences being studied concurrently at the Second
level.
Examination committees to prepare the terminal examinations were drawn
directly from the syllabus committees for the firmly stated purpose of ensuring
that the examination advanced rather than hindered the intentions of the syllabus.
Although considerable efforts were made to keep the four-year syllabus of integrated
science in the forefront of the deliberations by the senior science syllabus
committee, it might be argued that a higher degree of correlation might have been
possible had the two syllabuses been prepared by the one committee.
It can, however, be said that a high correlation between the two courses was
achieved in the text<strong>books</strong> written, because the project has been controlled by the
one chairman and group of editors and had substantially the same authors, all
thoroughly familiar with the plan and content of each of the <strong>books</strong> and syllabuses.
This has also assured a continuity of purpose and identity of method.
A.2.3 Stage 1: Integrated science
One of the main features of the new education scheme was the preparation of
youth for life in this scientific age, the preparation of youth to live in and understand
better the world of tomorrow, a world in which the boundaries of the
individual sciences are becoming increasingly indistinct.
Previously many students grew up without any science education, and thus
without the benefit of that particular approach to rational inquiry exemplified by
scientists, known as the 'spirit of science'.
To most adults space rocketry, the atom, electroniccomputing, modern biology,
synthetic fibres and the multitude of other advances that science and technology
have provided within this century are mysterious innovations of which they know
nothing and which they accept mainly with a sense of wonderment. Neither have
they been made aware that the spirit of science, whose characteristics include a
longing to know and to understand, a questioning of all things, a searching for
data and for relations among them that may give them meaning, a demand for
objective verification, a respect for logic, a consideration of premises, of consequences
and of alternatives, can provide the basis for belief. action and reform
in all aspects of daily life.
If this state of affairs were permitted to continue, the population would soon be
split into two kinds of citizens: those who know, and those who don't; those who
can adapt themselves to the scientific age, make use of it and live a full life in it, and
those who cannot and would therefore be relegated in time to a second-class
existence.
295 Integrated and Coordinated Science Courses in New South Wales

The solution had of course been obvious for some time: to prepare youth for a
successful life in a scientific age, each of them must be given the opportunity of a
grounding in basic science instruction in which the spirit of science is kept always
to the fore.
The Wyndham scheme provides that students shall receive five science instruction
periods a week. Furthermore every student is required to take the new
science course during the four years leading to the School Certificate. The course
is, as mentioned previously, taught at various levels, Modified, Ordinary, Credit
and Advanced level, to cater for the varying abilities of students who absorb this
knowledge.
The scheme provides that this ‘science’ course should not only educate students
in one scientific subject alone, such as <strong>physics</strong>, chemistry, biology or geology, but
that these four subjects should be taught in integrated form, as a conceptual unity,
in one course. The student should be able to view science as a whole and not look
upon it as ‘bits’. In addition, the integrated course should provide a maximum
amount of basic general knowledge for those whose only science instruction in
life will be this course, and a maximum scope for specialization for those who wish
to go further.
The four-year integrated science syllabus came into effect some eight years ago.
Because of the haste with which the N S W government decided to implement the
Wyndham scheme, the syllabuses for the integrated science course, along with
syllabuses for all other subjects, had to be prepared in a period of time which was
far too short.
The N S W Education Department’s Secondary-School Board appointed a
School-Certificate Science Syllabus Committee which had the difficult task of
drawing up the special syllabus. This committee chose as its members the leading
secondary and tertiary science teachers of the community, with proper dominance
given to practising secondary-<strong>school</strong> science teachers. There is no reason to
believe that the members of this committee could have been bettered in N S W or
in fact had they been chosen from throughout Australia. They were as representative
a group of dedicated, knowledgeable science educators as existed in this
country. The work these teachers performed and the speed and success with which
they performed it was most creditable. By January 1962 the first-year syllabus
was ready for teaching in the <strong>school</strong>s that year; by 9 November 1962 the remainder
of the four-year integrated science syllabus was completed.
It will be relevant to refer to some of the major ideas written into the syllabus
(and hence the text<strong>books</strong>) and its accompanying notes. The preamble includes
among the basic aims ;
To make students look around and see things previously unseen and seek explanations for
these things and to show them that science can lead to satisfying interpretations.
To have students seek such interpretations for themselves and to show them the experimental
technique used in science in searching for solutions.
To give students a store of related general principles which they can use to interpret the
physical world for themselves.
To give students an understanding of the scientific attitude and an appreciation of its
cultural value.
296 Case Histories

Teachers are invited to present the course so as to stress the unity of nature, the
recognition and application of concepts common to several sciences and the
interdependence of the sciences. Traditional deadwood was ruthlessly eliminated
and students were to be taken to ‘the frontiers of science’ and shown the ‘big
ideas ’ which were energizing modern science. In particular. three major concepts
were to form the all-pervading essence of the course to which teaching would be
continuously related. These were the concept of energy, the particle model of matter,
including the interaction between particles, and the spirit or style of science.
Other important concepts were: energy in life processes, adaptation in living
organisms, evolution, the relation of chemical change to changes in energy content,
the explanation of chemical behaviour in terms of energy, bonds and structure
; and electromagnetic radiation, fields of force, momentum and its conservation,
and the continuity of geological processes throughout geological time.
The course was to be based strongly on experiment and observation. with
student involvement, and with stress on the proper evaluation of evidence. The
syllabus rejects practical work which merely consists of determining known constants
or verifying known laws in favour of problem emphasis which encompasses
these facts and laws. The use of instruments and techniques were to be taught
when these werenecessary for the investigation of appropriate experimental problems
on hand. Mathematics and mathematical problems were to be introduced
only where essential for the proper understanding of a basic principle, the teacher
being free to decide this matter for himself. The syllabus committee could see no
value in the traditional mathematical gymnastics involved in ‘ ringing the changes ’
on standard formulae. Explanations in terms of the major basic principles were
intended to be emphasized at all times.
In the Modified and Ordinary levels, students’ prescribed work was to be
treated qualitatively, but for other students certain vital quantitative work was
prescribed. The teacher was, however, free to introduce quantitative methods
wherever these served better in arriving at basic understandings.
The syllabus gives great importance to scientific method and spirit and states :
‘The treatment of scientific method and attitude wil form part of the teaching of
every topic.’ This has as a corollary the study of the evolution of modern concepts
to unify the ever expanding store of knowledge and a recognition of the service
rendered by outstanding men at significant periods. Students were to realize that
science belongs to all men and is truly international. Similar emphasis is given to
consideration of the way in which science affects society and the lives of common
men. The syllabus committee tried to relate the content to the students’ own
environment and times and to have it harmonize with the natural interests of
adolescents without dissolving into the woolliness often associated with general
science courses. Much work previously considered unsuitable for treatment with
students at this level was included.
By demanding an academic rigour appropriate to the understanding of
students and being initially selective in the material included it was hoped to provide
a satisfxtory basis for later studies of a more rigorous specialized kind. The
syllabus was different, it was new. it was modern.
297 Integrated and Coordinated Science Courses in New South Wales

The initial reaction to the first-year syllabus was one of dumbfounded silence.
The following year the silence was broken as teachers began appreciating the
gigantic task before them, a task for which they and the <strong>school</strong>s were almost
totally unprepared, a point to be discussed later. Criticism, which appeared to be
that of the integrated syllabus, came thick and fast as former teachers of biology
were asked to teach the <strong>physics</strong>, chemistry and geology sections of the new syllabus,
and <strong>physics</strong> and chemistry teachers to teach the biology. But this was not a criticism
of the syllabus; instead it was a criticism of the fact that neither the <strong>school</strong>s
nor the teachers had been adequately prepared, through no fault of their own, to
teach the new and exciting science.
Looking back nine years, in retrospect it is evident that, though the original
four-year integrated science syllabus was not perfect in detail, it made an exciting
and revolutionary departure from the previous traditional syllabuses. It has profoundly
influenced thinking in regard to science teaching, examining and science
courses in general. Because the course began in 1962, immediately after the syllabus
had been written, judgements in those days were naturally coloured. Problems
associated with such external factors as facilities, equipment, teacher shortage,
qualification and experience, tended to emphasize the deficiencies and obscure
the virtues of the new scheme and syllabuses.
In the light of five years’ experience of both pupils and teachers, the four-year
integrated science syllabus was carefully revised during 1967 to reduce its bulk,
mainly at the Modified and Ordinary levels, and to remove some anomalies which
had become evident. It is surprising how little of the original syllabus had to be
changed and this speaks most highly of it. The text<strong>books</strong> covering these courses
were also completely revised for 1970 in keeping with the revised syllabus.
Since the course has now been taught for nine years some reasonably firm
judgements may be made with regard to it. It can be stated firmly that School
Certificate integrated science has won acceptance amongst N S W pupils and
teachers, and that the integrated approach to junior science has been ineradicably
established in N S W. It has quickened the interest of both pupils and teachers who
are gaining from it far greater satisfaction than was ever obtained from the previous
traditional courses and, furthermore, an entirely new species of student is
resulting from these courses.
Standards of achievement, as revealed by the public terminal examinations, are
satisfactory and there is clear evidence that the wider aims of the course are being
given increased emphasis. As teacher mastery over the course increased so did the
emphasis on experimental work, field work and scientific method, as was the intention
of the syllabus.
All this is not to say that a number of nagging problems do not still remain in
regard to Stage 1 in N S W, but largely these are not shortcomings of the scheme or
the syllabus. These problems centre mainly around aid, equipment and laboratory
shortages, teacher shortages and inadequate teacher training and preparation, all
matters of money and not content or philosophy.
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A.2.4 Stage 2: Senior coordinated science
The syllabus to cover the coordinated two-year science course for the fifth and
sixth years was prepared by a science-syllabus committee chosen by the N S W
Board of Senior School Studies. Membership of this committee was again chosen
from among the leading science educators of the State with due emphasis now
being given to representatives from tertiary institutions. This was in keeping with
the more advanced level of the subject material to be covered and also with the
fact that many of the students at the senior level would be using their fifth and
sixth years as a preparation for tertiary studies.
The senior syllabus, like the junior one, was again prepared in haste and under
considerable pressure to have it out in time for the first senior <strong>school</strong> year,
namely 1966.
The approach to the senior syllabus recognized the greater maturity and selectiveness
of the students remaining in the fifth and sixth years, the growing importance
of theoretical considerations and the inevitable tendency towards a more
specialized study of science. Subsequent tertiary studies, while not being allowed
to dominate the syllabus entirely. were now kept much more in mind.
Scientific method, experiment, and observation were still recognized as vital
elements but stress was now laid on fewer experiments being conducted, each
being more meaningful and with a more exhaustive theoretical treatment of the
evidence flowing from them. Quantitative studies were given a much enhanced
status and in many cases this simply involved returning to concepts already
covered qualitatively, or in a very simple quantitative way, in the junior course
and providing a more rigorous theoretical treatment. But in this course, also,
mathematics and instrumental techniques were intended to be used as tools
for deeper understanding rather than ends in themselves. Again mathematical
gymnastics were not encouraged and the derivation of formulae or equations of
basic laws, while essential to initial understanding, were not to be made subjects
for rote learning. The examination committee indicated that at the terminal
examination it would aim to assess understanding of principles rather than the
reproduction of memorized proofs.
Following the line of thought of the junior syllabus, the senior course was
firmly based on modern ideas active on the frontiers of science, on a limited
number of very basic principles, on explanations rather than descriptions and on
the elimination of traditional deadwood. As mentioned previously, in the junior
syllabus there is included much work previously considered unsuitable for treatment
with students at this level. The same approach was followed with the senior
course, which includes a considerable number of basic ideas previously considered
beyond normal <strong>school</strong> courses at any level.
Views on the interdependence of the sciences written into the junior syllabus
were just as firmly expressed in the senior syllabus. However, close integration
was not considered as practicable at this level and the course was planned as a coordinated
study of the sciences, with each science supporting and illuminating the
other. The basic importance of<strong>physics</strong> and chemistry to all science was recognized
and the major common concepts were written into a compulsory core. The senior
299 Integrated and Coordinated Science Courses in New South Wales

committee equally firmly rejected the image of students highly specialized in one
science but relatively ignorant in others. The separate sections of the syllabus
explicitly or implicitly recognize the unity of science and the general convergence
of scientific thought towards a fundamental understanding of the universe.
An examination of the basic concepts treated in the junior and senior syllabuses
reveals close identity with some understandably sophisticated extensions. For
example the senior <strong>physics</strong> syllabus echoes the view of the junior syllabus when it
states :‘Physics is not to be considered as a subject which consists of an accumulation
of large numbers of independent laws. The foundations on which the subject
is built are remarkably few.’ It then re-affirms the importance of such basic ideas
as the particle view of matter, fields of force, electromagnetic radiation, the laws
of motion and energy. To these it adds the importance of the constancy of the
speed of light. The student is given an elementary introduction to the concept of
quantum mechanics and special relativity as well as a number of other concepts
normally not taught at the secondary-schoo level.
The senior chemistry course has substantially the same conceptual basis as the
junior course, but with stress now being placed on quantitative considerations and
extensions being made into areas such as the periodic table and equilibrium. In all
sections there has been a severe selection of material with the exclusion of topics
not directly contributing to basic understandings. Scientific method and attitude
are again stressed with emphasis on the nature of scientific models.
Teachers, already reeling under the impact of the junior science syllabus, and
making valiant efforts to cope with it, were suddenly hit with this new and in
many cases exciting and radical syllabus, but at a considerably higher level than
that which faced them at the junior level. This resulted not only from the fact that
the senior syllabus was carrying on from where the radically new junior syllabus
left off, but also from the fact that the students were staying on in <strong>school</strong> for an
additional year. With only months to study the syllabus before beginning to
teaghit in February 1966, the secondary science-teaching community was shocked,
shocked in a way it had never been shocked before! The problems of the junior
course paled in significance in comparison with those of the new senior course.
The junior science course and its problems were now easy compared to that of the
senior one. Faced again with grave shortages of equipment, space, teachers’ aids,
an extra <strong>school</strong> year, and hence almost invariably inadequate teacher numbers
and preparation for the higher level, the science-teaching community in many
cases panicked. Logical argument and deduction became difficult or impossible
and especially so since there was no meaningful system of course evaluation in
effect. Almost everything in sight was attacked, the scheme, the syllabus, everything
except the thing which should have been attacked, the shortage of adequately
trained teachers.
But here again, what about the Wyndham scheme, or the coordinated senior
syllabus? Were they so much at fault? It is true that the original senior syllabus
was, like the original junior one, not perfect. However, it was superior to anything
seen previously in the <strong>school</strong>s of NSW or the other states of Australia.
Curriculum-reform groups elsewhere were impressed by the modern and forward-
300 Case Histories

looking aspects of the syllabus. It was exciting and contained numerous sections
which they felt they would include in their own syllabuses. Here now, for the first
time ever, was a modern, integrated and coordinated science course spanning the
whole six years of secondary <strong>school</strong>ing.
No one, however, disputed that the senior syllabus, like the junior one, would
need to be considerably amended after an initial run; yet the main difficulty was
that of insufficient and inadequately trained science teachers capable of coping
with the new syllabus.
It is even suggested that NS W should drop coordinated senior science and
return to teaching single science subjects, and furthermore use courses tailored
for entirely different needs than those of NS W. This suggestion is made in spite
of the fact that the overseas countries whose courses are suggested are themselves
endeavouring to change over from these to coordinated sciences. They are
also moving as quickly as possible towards implementing integrated junior
science at Stage 1. N SW had already done this successfully and coordinated
science had been the next logical step.
There was no doubt that the new coordinated Stage 2 senior syllabus needed
amendment badly and in addition was too long; even the best-prepared teachers
were unable to cover the material adequately in the periods allocated. In many
instances practical classes were cut or not given at all.Interim amendments have
been made and the whole Stage 2 senior course is now in the throes of being
thoroughly looked at and variations attempted. A substantial increase in period
allocation will undoubtedly be made. This should not only allow the teacher and
student to proceed at a more leisurely pace, but also permit the students to devote
a great deal more time to practical work. Steps wil probably also be taken to
ensure that adequate and continuous course evaluation wil go hand in hand with
the revised senior courses.
None of this, however, wil solve the really crucial issue at stake, namely that of
inadequately prepared. and insufficient numbers of, science teachers. With almost
any senior syllabus carrying on beyond the present junior one the present science
teachers in N S W wil still be unable to cope, for the simple reason that there is an
insufficient number of them. Of the existing ones, most have not been adequately
trained or prepared. In the meantime, not only wil the senior courses continue to
suffer but the junior ones as well.Because of the greater difficulty of the senior
course (after all,the students stay on for an extra year!) the better science teachers
are gradually being transferred from teaching the junior course to the senior one,
where in many instances they are unable to cope. The result has been relatively
poor teaching of both the junior and senior courses, and because of this many
students’ keen interest in science is so dampened at the junior level that they drop
it in their fifth year. The serious consequences of this are still to be appreciated by
our community.
The present temporary difficulties in Stage 2 senior science in NSW should
serve as a warning to those who may believe that major curriculum reforms can
be achieved smoothly without previously making a major effort in teacher preparation.
On the other hand, the excellent results being achieved with the Stage 1
301 Integrated and Coordinated Science Courses in New South Wales

junior four-year integrated science course prove that major reforms can be
implemented with success in relation to students, teachers and parents alike.
A.2.5 Conclusion
The implementation of a major educational reform such as Wyndham science
does not end with the preparation of a syllabus and text<strong>books</strong>. Unfortunately, as
the Australian community is now slowly beginning to realize, there is much more
to it than that.
Probably one of the most vital aspects is that concerning the preparation,
training and retraining of adequate numbers of science teachers who can cope
with the new and revolutionary courses. It is here, in its early stages, that the new
N S W science courses ran into severe difficulties. The government of the day
simply did not appreciate the magnitude of the task at hand, nor did it make
available the substantial finance necessary for teacher training. The result was
predicted by many educationalists and it was not surprising that thousands of
teachers went through a difficult period in the early years of the course. It was
obvious that, once the new courses had been decided upon, a large-scale programme
of science-teacher in-service courses should have been embarked upon
and concerted efforts made to expand greatly the number of adequately trained
science teachers. The teacher problem is now slowly being rectified but it is evident
that it cannot be satisfactorily overcome until large numbers of the Wyndham
science students themselves become the teachers of it.
The problems of the provision of additional classrooms to cope with the extra
year at <strong>school</strong>, and the provision of additional science laboratories and new
laboratory equipment to cover new experiments brought in by the new courses
and so forth, also gave cause for concern.
Then, too, there was the question of the provision of technical assistants for the
science teachers in order that they should be able to cope adequately with the new
laboratory experiments and lecture demonstrations. The present severe teacher
shortage in N S W is being further accentuated by utilizing the precious skill of the
few teachers available to carry out tasks which could more easily be carried out by
technicians with far less training.
There are further needs in direct relation to the syllabuses and text<strong>books</strong> covering
them. Text<strong>books</strong> for students and manuals for teachers are not sufficient
alone, but must go hand in hand with the development of visual aids such as film
strips, experimental apparatus and new experiments to cover the courses. All of
these are not one-shot affairs; the courses are living affairs and should be in the
process of being developed and improved continuously. New ideas should be tried
out; experiments designed to cover them, then introduced if they are good. However,
all ofthis requires considerable effort, effort on a full-time basis by specialists.
This total effort, sometimes called curriculum development, is expensive, but
must be carried out if the new courses are to be a success. Considerable effort was
and is being made by the textbook group and others to develop new experiments
(and these are included in the texts) as well as visual and other aids. However, it is
believed by the group that much still remains to be done in this field for the course
302 Case Histories

A.3
to achieve the high potential it is capable of achieving.
Finally, how does one really assess the success of a new curriculum? Here is a
field, course or curriculum evaluation, which is wide open for research and study,
and one deserving of considerable support if the changes made are to be honestly
assessed, Unless such evaluation is made on a continuing basis, there is danger
that we shall in the future have a repetition of recent events here and overseas,
where whole courses are in threat of being thrown, or are thrown, overboard
because of the shortcomings of only a part of the course or even of associated
aspects. One must be able to determine with precision which part, if any, of the
course anatomy requires surgery before embarking on it. Without adequate and
continuing evaluation procedures, this cannot be done.
The Nuffield programmes in the United Kingdom
Kevin Keohane
Much has been written of the great rash of curriculum development that characterized
education throughout the world during the 1960s. We hear of the apparent
‘ stunning’ of the American mind that followed the launching of the first Russian
Sputnik. as though this were the essential precipitating factor that ensured a
serious reappraisal of the curriculum in science and mathematics. This may or
may not have been true in the United States. In the United Kingdom it was of
negligible import. Perhaps what is more amazing is not that education was relatively
uninfluenced by the event, but that it had taken so long for major curriculum
study tobecome established when the problems had been identified for many years.
In England. there is no centralized direction of the curriculum, either in terms
of balance between areas of learning that are studied in <strong>school</strong> or of the content
within these areas. This is a freedom that some in other countries may envy,
although there is a view that the freedom is at least partially illusory. External
pressures are able to erode the freedom almost as effectively as central direction,
and none is more powerful in this respect than the effect of examinations. In
Britain there appears to be an almost pathological attachment to the public examination.
Indeed it is almost a sine guu non that any British group discussing the
curriculum will within ten minutes raise the subject of examinations, and it is
perhaps symptomatic that in this contribution the topic should be raised within
the first paragraphs. The two torments of life in Britain have been the examination
and the weather, and the Englishman has felt that he could do little about either.
The problem has been with us for over a hundred years. In the mid-nineteenth
century, very soon after the first public examinations for <strong>school</strong>s were set by
Oxford and Cambridge universities, a parody on Lewis Carroll’s ‘Walrus and the
Carpenter’ was published. Amongst its twenty or more verses, sentiments were
expressed that rang desperately true even a decade ago.
The papers that they finished lay
In piles of blue and white.
The candidates did all they could
And wrote with all their might;
But though they wrote it all by rote,
They did not get it right.
303 The Nuffield Programmes in the United Kingdom

Many years later Lewis Carroll himself continued the same theme in Sylvie and
Bruno: ‘You may remember that we regard our pupils to be a kind of Leyden Jar
that we charge up. We draw off one magnificent spark which sometimes cracks
the jar, but no matter that. We put it away on the shelf and we label itJirst class
spark.’ It summed up beautifully the effect of the external examination at that
time. Our teaching of science was principally directed by it; science in <strong>school</strong>s was
treated almost as though everyone who studied science would continue with it to
university and beyond. The <strong>school</strong> syllabus was essentially a syllabus of content
for examination aimed principally at selecting candidates for university entrance
on the basis of scientific knowledge.
In the early part of this century the eminent physicist, J. J. Thomson, was
charged with the responsibility for investigating the supply of scientists in
Britain. With his committee he came to the conclusion that science should be part
of the cultural studies of all children in our <strong>school</strong>s, and that it should be aimed at
presenting an experimentally based introduction to scientific method and thought,
suitable for all in the community and not of significance only to those who required
science as a prerequisite to vocational or professional studies. But little
obvious change occurred.
There were perhaps two specially important influences that were felt between
the wars. Firstly there was the increasing part played by teachers in the formulation
of examinations and membership of the boards that controlled them.
Secondly there was the growth of an active professional association of science
teachers. The two factors together combined to form the strongest pressure for
curriculum change in the period after the second war.
It was largely as a consequence of the work of the curriculum-study groups that
were set up by the professional associations of men and women teachers in science
that the Nuffield Foundation invested enough capital to embark on major
curriculum-development studies. The initiative came at a time when the educational
system as a whole was seen to need, and to be on the brink of, change. The
reorganization of <strong>school</strong>s, the elimination of selection and the movement towards
comprehensive education that has been growing in the last ten years came to be
seriously discussed at much the same time as the beginnings of these major curriculum
studies. It is difficult, in retrospect, to know whether the priorities would
have been chosen differently if the reorganization that has subsequently occurred
had taken place earlier, but the Nuffield Foundation commenced its work in
those areas in which the professional associations had already made a start:
curriculum study in the separate sciences of <strong>physics</strong> and chemistry and biology for
more able children in the eleven to sixteen years age range.
Three separate five-year courses of study in the separate sciences of biology,
chemistry and <strong>physics</strong> were developed under the Nuffield auspices. An attempt
was made to devise courses primarily laboratory-based, with the child learning
much by personal experiment and inquiry. Content was not considered to be as
important as the approach to understanding, but it was chosen to be modern,
relevant to the child and forming a coherent related pattern of topics. These efforts
would have been in vain if they had not been accompanied by an examination
304 Case Histories

which set out to assess those skills and abilities that the projects had identified as
desirable and achievable objectives. With the ready cooperation of the examination
boards, special examinations were established for use with the projects and
they have probably played a not insignificant part in encouraging the changes that
the boards have themselves subsequently made to their own ‘traditional syllabus’
examinations.
These initial three projects were followed by others. Firstly. one for the primary
<strong>school</strong>s, for the children who commenced at five years and go through primary
education to about the age of eleven. A highly unstructured approach was
adopted with children being introduced to scientific activities through their own
personal investigation of the environment.
Primary Science was later followed by a second project in Combined Science
for the eleven to thirteen year olds in the first two years of secondary education.
Many teachers preferred to treat science as a unity in the early secondary-<strong>school</strong>
years. It was therefore appropriate to attempt to fuse the major ideas in elementary
secondary science in this Combined-science project. Although the eleven to sixteen
year old materials (Nuffield 0-level) were designed essentially for the upper
ability groups, the changing reorganizational pattern had been producing, in
some <strong>school</strong>s, classes of wide ability ranges during these early secondary years. It
was therefore decided soon after the Combined-Science Project started work to
extend its brief to include children over a very wide ability range.
The next, and perhaps the largest. of the projects to be developed has been a
three-year integrated programme in secondary science for those pupils in the
thirteen to sixteen age group who were unlikely to proceed to public examination
at 0-level. This is the group which comprises nearly 70 per cent of the children
who formerly would not have been selected for inclusion in the grammar-<strong>school</strong>
ability ranges. The provision in science that had been made for them in <strong>school</strong>s
had frequently been less lavish than their grammar <strong>school</strong> colleagues enjoyed in
terms of equipment, laboratories, courses and teaching. A major decision was
made at the outset that an attempt should not be made to produce materials for
the separate sciences. The scheme was to be one of quality in its own right and not
to be seen as a diluted version of that which was provided for the more able group.
The outline programme was based on eight themes, from which the teacher could
select and on which he could concentrate to varying degrees, themes that were
chosen from both the biological and physical sciences with the important criteria
of significance to the pupil and relevance to their applications in, and impact on,
society.
Beyond the age of compulsory <strong>school</strong> attendance an increasing proportion of
pupils aged sixteen to eighteen remain in the secondary <strong>school</strong> in order to proceed
to further and higher education. Within this age group there has been a tendency
for studies to be narrowly confined to two or three subjects within either the arts
or the sciences. Considerable concern has been expressed (see for example the
Dainton Report and the Swann Report) at the consequent high degree of specialization
and also the adverse effects that are referred back into the earlier secondary<strong>school</strong>
years. As an aid which might reduce this specialization in the post-sixteen
305 The Nuffield Programmes in the United Kingdom

age ranges, it was initially decided to develop two courses of study in science, one
in the biological sciences (botanists and zoologists had no heart for separate
disciplines) and one in the physical sciences. A student would be able to select a
full range of studies within the sciences and mathematics which would leave
options open for higher education in both pure and applied, physical and biological
science, or he could include some study of the humanities without closing
the door on an ultimate career in science or technology. Change seldom comes
about quickly within the English system and it was soon realized that in the
physical-science field it would be essential to continue for some time to offer the
choice of the separate disciplines of <strong>physics</strong> and chemistry. There are therefore
four Nuffield Projects at this advanced level : biological science, physical science,
chemistry and <strong>physics</strong>.
As with all the Nuffield Projects, the programmes have been developed by
teams of teachers seconded from their <strong>school</strong>s and assisted to a lesser degree by
their university teaching colleagues. Each team has submitted its proposals to a
consultative committee composed of teachers, university dons, members of Her
Majesty’s Inspectorate and representatives of industry. Outline schemes have
been discussed; materials have been written and put on trial in a large number of
<strong>school</strong>s. The subsequent feedback has been used to modify the materials prior to
publication.
A.3.1 Implementation
As each of these projects is published, there wil be the major problem of the
seventies : the implementation of curriculum innovation. The consequences to
industry that follow technological innovation have been far more clearly identified
than has the impact of curriculum innovation on education. The manufacturer
not only sees the logical sequence of research, development and pilot-plant production
as essential precursors to full-scale manufacture, but also realizes that
they are only the beginnings of his investment if there is to be any chance of a
satisfactory uptake of his new product. Distribution, sales and, above all, aftersales
service must follow, and any industrialist wil tell you that this is where the
real expense can begin. It is essential expenditure on top of the inevitable cost of
replacement of plant and re-education of personnel.
This analysis has an interesting analogue in education. We have seen that there
are some parts of the world where a curriculum is thought of in terms of a
scheme of teaching which may be accepted or adopted in an entire province or
state. Adoption often means that a teacher is tied to a particular scheme with
little or no choice. For good or for bad when change occurs the old goes out and
the new comes in. It is indeed an example of innovation through displacement. It
is a procedure to which Britain is unaccustomed. If curriculum change occurs it
is by invasion. There is a belief in this principle of freedom of choice, even though
it may be partially illusory. Every new scheme has to convince each teacher,
despite pressures both conservative and radical, that the change is in the best
interest of the child. It is probably true to say that when the Nuffield Foundation
306 Case Histories

set out on the initial major curriculum-development exercises there was not a full
realization of all the steps that would follow the development phase. Just as the
precise steps that lead to technological innovation can be identified, so they can
assist us in our attempt to see more clearly the implications and the steps that are
necessary if curriculum innovation is to stand a chance of success. How far is
economic risk an important factor inhibiting curriculum change ? What are the
other external pressures? Do they only retard change or can they be influential in
encouraging change ? What sort of after-sales service and re-education needs to
be provided to make a practical realization of innovation? How far can changes
be evaluated and what are their important consequences and implications to
society, systems and institutions? The questions are many and numerous and
only a few of them can be dealt with here.
A.3.2 Assessment
Traditionally it had been considered by examination boards that they had no
responsibility for the way in which topics of a syllabus were taught; this was the
responsibility of the teacher. But views have changed; there is now a more general
acceptance that syllabuses and question papers (of whatever kind) must, and do
inevitably, affect methods of teaching the pupils preparing for the examination.
In the traditional style of examining there was a pretence that such effects did
not exist; indeed the system was based on this assumption. The formulation of an
examination on a traditional syllabus must lead to an emphasis on factual
material. Because such a syllabus lists factual material, teachers are discouraged
from trying to develop a variety of relevant abilities and encouraged instead to
concentrate on helping their pupils to acquire the facts necessary for success; and
who can blame them for attempting to ensure what is expected from them? In the
absence of a definition of the abilities to be assessed teachers can only rely on past
papers as a guide to their teaching.
Furthermore, the wide choice of questions conventionally offered reflects the
admission that the candidates wil not cover all the syllabus. It is not a single paper
so much as a number of different papers depending on the questions chosen, and
yet the candidates have all to be listed in a single order of merit.
Another problem arises which can be aggravated by trends towards continuous
assessment. Examinations, whether they be internal or external to the <strong>school</strong>, are
dependent on a supply of examiners skilled in the art of examining specifically to
the pre-determined ends that are now being sought. Itis a fact that most of us find
some difficulty in acquiring the know-how which enables us to assess how far we
are achieving the aims of our teaching. The experience of curriculum development
in Britain has shown the need for a deliberate and specific policy of training for
this rather than the casual acquisition of ability in these skills. In Britain at least
the problem is far from decreasing. The growth of a Certificate of Secondary
Education (taken by those children normally below the ability range that is
entered for 0-level examinations) places an emphasis on examinations that has
not been too severe in the past on either the teacher or the less academic child. In
the Secondary Science Project a need has already been found to offer assistance to
307 The Nuffield Programmes in the United Kingdom

~
teachers in the formulation of questions and examinations of the Mode-3 type*,
and the Schools Council has funded an investigation into the best approach to
this assistance in step with the Nuffield curriculum programme.
A.3.3 Education for change
In the sequence for industrial change outlined above the implementation of change
is heavily dependent on the service that is provided both to equip the consumer for
change and to offer a post-change service. In the educational context this means
that we must ensure that the teacher and the teacher in training have the opportunity
of themselves being educated for change. The magnitude and costs of such
programmes can be many times that of the curriculum project itself and the
availability of ' spear-head' tutors to lead the in-service training needs most careful
advance planning.
But if retraining presents us with problems, so too does the system for the professional
education of new teachers in the light of curriculum renewal. The impact
of innovations can be all the more profound if we get our initial programme of
training in harmony with modem developments in the curriculum. It may be that
the very philosophy of teacher training must be reoriented to reflect the recent
thinking of the curriculum by breaking down the barriers and developing closer
integrations between the educational and the main discipline studies in the
training course.
A.3.4 Assistance for the teacher
These are changes that are within our power as educationalists to achieve if the
spirit is willing. However, the implications of curriculum innovation to the classroom
teacher can be impossibly severe if the wherewithal is not given to him to
teach a progressive, laboratory-based programme. It is not sufficient, important
as it is, to provide finance for <strong>books</strong>, equipment, teaching aids, retraining and the
capital re<strong>source</strong>s for storage of apparatus; the teacher must be given time to play
his proper role as a guide to individual learning. And this means availability of
adequate and trained technical and clerical assistance.
A.3.5 The future
Much has been accomplished in the past ten years. A period of consolidation will
probably now develop, although already one can see clearly the direction in which
future changes in teaching in Britain wil occur. Should not our aim for the 1980s
(and it is not too early to plan) be an integrated programme of teaching across the
sciences for all children before specialization in the later years of secondary education?
A start has been made and a project funded by the Schools Council has
just begun its work. Problems can readily be identified, particularly with regard to
teacher confidence in presenting such broad programmes, but is not this integration
the star towards which we should be aiming?
* Mode-3 is the type of examination set and marked internally by the teacher with external moderation
308 Case Histories

A.4 PS S C and its adaptation for use in Scandinavia
K. G. Friskopp
A.4.1 How PSSCdeveloped
In 1955 the result of an investigation was published in USA, showing that only
4 per cent of the high-<strong>school</strong> students chose to study <strong>physics</strong>. This shocking result
was one of the reasons why the Physical Science Study Committee (P S S C) was
formed with the main object of working out a new <strong>physics</strong> course. The argument
was that the current courses and text<strong>books</strong> were to a great extent responsible for
the poor reputation of <strong>physics</strong> as a <strong>school</strong> subject.
The work on a new <strong>physics</strong> course started immediately, and in the <strong>school</strong> year
1957-8 the first parts of the course were used in pilot schemes. An extensive
system was built up to ensure a rapid feedback of the experiences from the field. In
1960 the first edition of the textbook appeared. in 1965 the second edition, and in
the same year an extension of the course, the Adaunced Topics Supplement. The
textbook was only one part of a complete set of teaching aids.
Up to 1965 more than three hundred physicists, teachers. technicians, film
personnel, etc. had contributed to the course. Altogether about five hundred
work-years have been spent in producing the course. The costs for the production
amounted to about six million dollars, and the money was received from the
National Science Foundation, the Ford Foundation and the Alfred Sloan
Foundation.
A.4.2 Some busic ideus in the PSS C course
One basic idea in the P S S C project was to build up a suitable <strong>physics</strong> course in a
rapidly changing society. To supply lots of facts which may become outdated or
completely uninteresting within a couple of years can hardly be correct. To train
students’ ability to acquire new science information and to solve new problems in
a constructive way must be as essential as to inform the students about current
physical knowledge.
It follows from this basic attitude that the course should be restricted to fundamental
and central concepts and relations considered to be lasting. But superficial
knowledge about these things is not enough. The teaching must lead to
real understanding which makes it possible for the students to use their knowledge
in creative thinking outside the topics treated. This understanding is not acquired
by merely learning definitions and mathematical deductions. In order to sharpen
and deepen understanding, extensive motivations and discussions are required.
Therefore the textbook must be a great deal more voluminous than a conventional
one.
But the aim of the teaching is not only to lead to knowledge of <strong>physics</strong>. It is
equally important for the students to learn how physicists work and how <strong>physics</strong>
knowledge is built up. That students are being trained in scientific methods has
its own value. The students must learn to ask questions. plan experiments to get
answers, collect data, draw conclusions and finally discuss the reliability of the
conclusions. Thus it is obvious that experimental work must be in the centre of
309 PSSC and its Adaptation for Use in Scandinavia

the teaching, and the discussions must be based on experimental evidence. The
best way of achieving this is for the student himself to carry out the experiment.
Second best is for the teacher to demonstrate it. A third possibility is to show the
experiment on a film or on television, and only if no other solution is left should
an oral or written description be given to the students.
Another characteristic of the PSSC course is the way the physical ‘laws’ are
treated. The physicist’s work does not aim at disclosing more or less hidden
general and exact physical laws. Such laws are, on the whole, not assumed to
exist. Instead his activity represents man’s attempt to describe and systematize his
observations of nature. Science is not static but resembles a building which is constantly
being rebuilt and enlarged. To describe the observations within an area of
reality a model is set up which can be a concrete picture of a more or less abstract
theory. No claim is made that the model should be an exact or final description. It
is only an approximation. But it has its value by connecting the experiences and
by giving impulses to look for new phenomena.
As new information is gathered the model may be modified or even abandoned,
not because it is wrong but because another one has been found which better links
all the experiences found within the area.
A.4.3 The construction of the PSSC course
The PSSC course was constructed as a complete <strong>physics</strong>-teaching system, intended
to be covered during one <strong>school</strong> year with about eight periods a week.
However, those responsible for the course were aware of the fact that the course
demanded more time. Experiences have shown that one-and-a-half to two years
were needed for a complete treatment. The average age of the students is between
sixteen and seventeen.
The central part of the course is the textbook for the students. According to the
basic philosophy the text is more wordy and mathematical formulae occur more
rarely than in most <strong>physics</strong> text<strong>books</strong>. Furthermore, the book contains considerably
less data and factual knowledge than a conventional book, especially
when classical <strong>physics</strong> is concerned. Technical applications are only discussed if
they have decisive influence on the development of <strong>physics</strong>.
The problem sections in the text try to fulfil the aim of training the students in
active scientific thinking. Beside problems to check and reinforce knowledge and
understanding there are many problems where the students’ ability to apply their
knowledge to new situations is trained, often within areas not covered in the text.
Acoustics is a phenomenon which is only treated in the problems sections, as a
topic where the wave model can be applied. Another frequent type is the openended
discussion problem where scientific reasoning should lead to more or less
far-reaching conclusions in a given situation. What is of interest here is the discussion,
not the result.
A laboratory guide and special equipment were prepared for the students’ experiments.
The equipment is very simple; there is a reason for this. The phenomenon
which is being investigated should not be obscured by too sophisticated
310 Case Histories

technical equipment. The experiments are designed to investigate essential physical
phenomena and relations. The guides are not detailed enough to make work
and data compiling possible without thinking. At first the problem is introduced,
then necessary instructions are given and finally a number of questions are put. To
answer these questions requires more or less advanced scientific thinking based on
the experimental results.
Some of the basic experiments in the course cannot be performed by the students.
They should be demonstrated either by the teacher or by a film.About fifty
teaching films were made. They are integrated into the teaching and are generally
on topics which need too much time or too complicated apparatus to allow them
to be demonstrated by the teacher.
A teachers’ guide also belongs to the PS SC project. It contains time schedules
for the course, commentaries on the text, information and discussion hints for the
lessons, experimental instructions, answers and discussions of the problems.
Lastly, and somewhat loosely connected to the course, is a series of monographs,
the Science Study Series. The <strong>books</strong> give a more detailed description of
certain areas of <strong>physics</strong> and are suitable for interested students.
A.4.4 The spreadrig of the PSSC course
During the end of the 1950s the member countries of 0 E E C (now 0 E C D) discussed
the technical development of their countries, and as one of the results of
this discussion a committee of experts was appointed to suggest a modernization
of <strong>physics</strong> teaching. In 1960 this committee put forward its report. A Modern
Approach to School Physics. In the report serious criticism was directed at <strong>physics</strong>
teaching in the member countries. The criticism referred to both the contents of
the courses and the methods of teaching.
One of the consequences of the report was that 0 E E C contacted P S S C to get
the P S S C project introduced to the member countries. A conference for all
member countries of OEEC was arranged in Cambridge, England, in 1961. The
object was to familiarize the participants with the P S S C course and to discuss the
possibilities of its use or adaptation in their countries.
This resulted in pilot courses in Greece, Yugoslavia, Italy and Spain, using a
direct translation, and in Norway and Sweden with a translated and revised
version. Stimulated by P S S C and by ideas put forward by the 0 E E C committee,
England started its own Nuffield Project in <strong>physics</strong>.
A.4.5 The Norwegian-Swedish triuls with the PSSC course
The Norwegian and Swedish participants at the Cambridge conference in 1961
agreed that the P S S C course should be tested in Norway and Sweden, but that
certain adjustments and additions ought to be made at the translation stage.
These views were reported to the Swedish Board of School Administration and
it was decided to start trials in cooperation with Norway in a number of invited
<strong>school</strong>s, beginning in the autumn of 1962 and continuing for five <strong>school</strong> years
(later increased by another year). The PSSC course was to be translated and
311 PSSC and its Adaptation for Use in Scandinavia

evised by a joint Norwegian-Swedish group of experts. In 1966 a new trial
started with a revised course based on feedback from students and teachers.
In Norway the teachers themselves decided if they wanted to take part in the
trials, but in Sweden selected <strong>school</strong>s had to enter. The fact that whole <strong>school</strong>s
were chosen in Sweden meant that the teachers involved were not just those who
were enthusiastic about the course. Their critical attitude meant that the course
was scrutinized effectively and in detail.
During the six <strong>school</strong> years of trials in Sweden about seventy teachers and
three thousand students were involved for a longer or shorter period. The new
trial which started in 1966 has so far involved about a hundred teachers and fourand-a-half
thousand students.
A.4.6 The revision of the textbook for use in Scandinavia
Since the P S S C course was written for a different <strong>school</strong> system than our own,
certain adaptations had to be made. The main differences between the high <strong>school</strong>s
in the United States and in Scandinavia justifying a revision were the following:
(a) The pupils in Scandinavia would experience three years of <strong>physics</strong> before
doing the course. Therefore certain parts of the P S S C course could be shortened
or even omitted.
(b) In Scandinavia more <strong>physics</strong> periods were available. The course could therefore
be increased, especially with technical applications.
(c) The Scandinavian students had a better mathematical background so the
course could be given a more mathematical structure.
(d) The <strong>school</strong>s in Scandinavia were well equipped and the teachers were used to
demonstration experiments. Therefore films were not needed to the same extent
as in the U SA.
The arguments above might have given reason for a thorough revision of the
original P S S C course. Still,the changes by the group of experts were on the whole
modest, since far-reaching changes might destroy the philosophy of the course.
The aim of the trial was to examine the value of the new attitude towards <strong>physics</strong>
teaching, not to test details such as the choice of topics or the order of the treatment.
The following is a list of the essential changes in the Swedish edition:
Part 1. The chapter on vectors was transferred to Part 3, and certain sections were
shortened.
Part 2. The chapter on optical instruments was increased and sections on photometry,
polarization and transmission gratings were added.
Part 3. The chapter on vectors, transferred from Part 1, was given a more mathematical
structure. On the whole more mathematics was introduced in the treatment
of mechanics. To Part 3 was added the chapter on angular momentum
inchded in the P S S C Advanced Topics.
312 Case Histories

Part 4. The American fourth part was divided into two parts, electricity and
quantum <strong>physics</strong>. More mathematics was introduced in the treatment of electricity.
A chapter on alternating current and on electronics was added.
Part 5. To the three original P S S C chapters on atomic <strong>physics</strong> were added three
new chapters on nuclear <strong>physics</strong>. The textbook was finished with a chapter on
solid-state <strong>physics</strong>. An appendix on relativity theory was also introduced.
No special laboratory guide was written. The experiments taken over from
P S S C got separate instructions, but it was further assumed that a great many
experiments already existing should be used. The trials should give an answer on
the need for laboratory instructions for the students.
Every participating <strong>school</strong> was provided with the American teachers’ guide
(which was not translated) to be used by the teachers. It was hoped the experience
would indicate how a Scandinavian guide should be written.
About fifteen P S S C films were bought and have been used in the original
language in the pilot classes. The film texts have been available in class sets.
Every summer a conference between the participating teachers and the group of
experts was organized to discuss the progress of the trials.
A.4.7 Evaluation
Despite the difficulties, it was decided in Sweden to try to make some kind of
comparative testing between the PS SC course and the conventional course, the
testing to be carried out in cooperation with the psychological department of the
teacher-training college at Malmo. A group of PSS C pupils and a comparable
group of pupils doing a traditional course were given introductory tests in <strong>physics</strong>
and in reading ability, supplemented by intelligence tests and interest tests in order
to normalize the material. In these preliminary tests, and during the discussions
on the continued testing methods. it was verified that no unbiassed methods to
test P S S C pupils in relation to pupils with the traditional course could be found.
It appeared however that certain details can be tested, for instance reading ability
and ability to tackle unknown problems. Such tests have been carried out in U S A,
Yugoslavia and to a certain extent Norway. Both in Sweden and in these other
countries the ability to read and understand an unknown text and to solve quite
unknown problems has been somewhat greater among students on the PS S C
course than among students doing the traditional course of the country.
One main reason for this may be that students on the P S S C course are continuously
trained to tackle unknown problems. It can be mentioned here that, in
spite of the fact that no treatment of heat is included in the PS S C course, students
of the technical gymnasium at Oslo have succeeded better in the course on heat in
the engineering examination than students on the traditional course, where a
complete treatment of heat with all its formulae is given.
Thus the evaluation of the P S S C course has mainly been done by more subjective
methods. Most of the teachers’ opinions have been collected at teachers’
conferences, but special question forms have also been used. A number of students
have also answered different questionnaires.
313 PSSC and its Adaptation for yse in Scandinavia

The teachers were asked their opinions about the PSSC course in 1964, 1965
and 1967. The question about which type of course the teacher would prefer if he
had a free choice was answered as in Table 10.
Table 10
Teachers’ choice in %
1964 1965 1967
Preference for the PSSC course 38 64 66
Preference for the conventional course 13 7 25*
Preference for a combination of the two courses 49 29 9*
* Conventional course here means the new gymnasium course introduced in 1966.
From the table it can be seen that the teachers have grown increasingly to like
the P S S C course. One reason for this may be that the PS S C philosophy has
gradually been found more acceptable to Swedish <strong>physics</strong> teachers.
From conference reports and from answers to questionnaires most teachers
agreed :
(a) Some sections of the textbook were unnecessarily wordy.
(b) The mathematical treatment (often additions in the Swedish edition) was
sometimes too difficult and took too much space. It was recommended that the
physical descriptions and arguments should be given in the running text without
too much mathematics, and that the hard mathematics should be given as a complement
in a box.
(c) Especially during the first stages of the trials many teachers definitely wanted
summaries in the book after every chapter. This attitude changed later on and the
opinion then was that the summaries ought to be written jointly by the teacher and
the students.
(d) Answers to the problems ought to be found in the textbook, with the exception
of problems leading to open-ended discussions.
(e) From the beginning the opinion was that relations and conclusions ought to
be emphasized in the text in order to facilitate the learning. This opinion was later
moderated as one of the aims of the course is to teach students to draw conclusions
themselves.
(f) It was strongly advocated that an extensive teachers’ guide must be available.
(g) Demands for more technical applications were put forward.
(h) Teachers complained about lack of time. This meant that too little time was
left to cover nuclear <strong>physics</strong>.
314 Case Histories

(i) As a rule the teachers had great difficulties in putting the class experiments at
the right moment of the teaching. The traditional timetabling with class experiments
strictly tied to certain half-class periods, often with a week‘s delay between
the two halves of the class, was completely inappropriate for the Swedish PS S C
course.
G) Large sections of the introductory part (Part 1) were considered unnecessary
in Sweden. It was felt the course ought to start with optics.
Students questioned in 1967 and in 1968 mentioned the verbosity of the book,
the mathematics, the need for summaries, and almost every student wanted
answers to the problems in the textbook.
The comments reflected a comparatively regular reaction from the students to
the P S S C course. Initially reserved, and sometimes negative, the attitude has
gradually changed and become more positive as the principles of the course
became clearer.
It is evident from questionnaires and from conference reports that the great
majority of the teachers taking part in the pilot courses have accepted the
principles of the teaching philosophy embodied in P S S C.
A.4.8 The revised course
On the basis of experience with the pilot course a new trial course has been drawn
up where the order is different: optics, mechanics, electricity, quantum <strong>physics</strong>.
This has various advantages. The optical concepts are apparent and easy to understand,
and the relations treated are simple and mathematically uncomplicated. A
start with optics therefore means a soft transition from the qualitative teaching of
elementary work to more quantitative teaching. By postponing mechanics the
students wil acquire ability to understand better the more complex concepts
treated in it.
In the revised course the time allocation is two and a half periods a week for
the first year, four periods a week in the second and third years. During the first
year most classes read the first part (optics). In the second year they read the
whole of part two (mechanics) and the first four chapters of part three (electricity).
In the third year they complete this part and do as much as possible of part four
(quantum <strong>physics</strong>).
Because of the central importance of class experiments a flexible system for the
timetabling of practical work has had to be introduced. A system of fixed
‘laboratory periods’ is unacceptable (see item i above). The not uncommon
system in Sweden, where the two halves of a class do their experimental work at
an interval of one week, is clearly not suitable for the new course.
Trials are continuing on this revised programme.
31 5 PSSC and its Adaptation for Use in Scandinavia

A.5 The Unesco Pilot Project: follow-up and adaptation in Argentina and Bolivia
R. E. Ferreyra
A.5.1
The teaching of<strong>physics</strong> in Latin American secondary <strong>school</strong>s
In too many <strong>school</strong>s <strong>physics</strong> is taught as if it were a rigid body of knowledge which
the student is supposed to memorize. The generally accepted method of teaching
is as follows : the teacher explains the lesson, he then talks and writes on the blackboard
and occasionally he performs a demonstration experiment. Pupils must
study the lesson in their text<strong>books</strong> and be prepared to repeat it during the next
class period. This regurgitation performance is, in most cases, used for grading.
Despite some excellent text<strong>books</strong> and good teachers, a major problem is that
many <strong>school</strong> syllabuses in Latin America are hopelessly overloaded and encyclopedic.
Most syllabuses reproduce textbook contents with no mention of those
attitudes, intellectual outlooks and laboratory skills considered to be desirable
acquisitions by the students through studying the courses. In several countries
these syllabuses are uniform for all the <strong>school</strong>s.
Teachers are required to cover very long programmes with forty to seventy
students per class, without a laboratory, without an appropriate budget for equipment
and with no guidance in ways to use time and materials effectively.
Even a good teacher is unable to teach <strong>physics</strong> as an exciting valuable subject in
the face of these limitations ! With no opportunity for post-graduate study
teachers in most Latin American countries lack even the chance to learn improved
teaching approaches. It should be added that, with student enrolment increasing
faster than the number of qualified teachers, <strong>physics</strong> is being taught more and
more by teachers with little or no training in <strong>physics</strong>.
A.5.2 The course designed by the Unesco Pilot Project on the <strong>Teaching</strong> of Physics: a
multi-media approach
The Unesco Pilot Project on the <strong>Teaching</strong> of Physics faced the problem of designing
a course based on laboratory experiments performed by the students as a
fundamental tool for learning. The challenge in this project was to find a way to
involve students as well as teachers in laboratory-oriented 1-rning.
Science was to be considered as a human enterprise aiming at an understanding
of the physical world, leading ultimately to a continuous broadening of knowledge.
The methods and materials were to be designed to motivate <strong>physics</strong>
teachers to face the problems involved in teaching a laboratory-oriented course.
Furthermore, the system had to be simple enough to be usable where neither
laboratories nor trained teachers were available.
The project decided that very simple inexpensive equipment integrated with
pzogrammed-instruction laboratory guides could provide the means for introducing
students, as well as untrained teachers, to meaningful laboratory work.
Thus teachers and students would be introduced to the fundamental procedures of
the scientific method: observing, experimenting, systematic pursuit of regularities,
the construction of models, the stating and testing of hypotheses, the deriva-
316 Case Histories

tion of physical laws, etc. The programmed laboratory was meant to be an aid to
help the student both in rediscovering the basic concepts in <strong>physics</strong> and also in
developing laboratory skills.
In addition film loops and television programmes would serve the purpose of
encouraging discussions and leading to a deeper understanding of concepts so
that they could be applied to new problems. This material would also give teachers
ideas for demonstration experiments and for new patterns of interaction with
their students in the class. In short the course advocated a multi-media approach
to the teaching of <strong>physics</strong>.
In 1964, after a year’s work in Sao Paulo on the first phase of the Unesco Pilot
Project, a group of about twenty-five Latin American <strong>physics</strong> teachers, with the
aid of some specialists provided by Unesco, produced the ‘Physics of Light’
course. Optics was chosen because the models that have been developed over the
years to explain the behaviour of light constitute a good introduction to the use of
the scientific method. The course consists of five programmed <strong>books</strong> (laboratory
guides) with 1892 frames, eight different kits (shoe-box size), eleven film loops (8
mm, silent) and eight television programmes (half an hour each). The set of kits
and texts was planned to provide a fully programmed sequence of learning
experiences built around the experiments performed by the student and the
interpretation he gives to them.
These materials were intended to be self-instructional, so they were tested at the
development stage to make sure that students could progress through the programme
without the assistance of the teacher. Self-directed study has important
implications for the role played by the teacher in the classroom. The teacher would
have time to study, to think, to help students either individually or in groups, to
promote discussions, to prepare demonstrations, and so on. In other words, the
teacher would be free to enrich the programme and take up a more creative role.
Teacher’s guides for the use of the films and television programmes were prepared
for that purpose.
A.5.3 Field testing and modi3cation of the multi-media approach
It was recognized that it was necessary to test the Unesco Pilot Project methods
and materials more widely to find out to what extent they were applicable to conditions
in Latin American <strong>school</strong>s, and to determine if they were adequate for
promoting desired changes in <strong>physics</strong> teaching. Since 1965 the course has been
validated by thousands of students in Argentina and Bolivia, and less extensively
in other countries.
Basic problems in testing in Argentinian <strong>school</strong>s. Early testing in Argentina, using
the first Spanish version of the texts, disclosed the following problems:
(a) Students who interrupted their experiments at the end of a working period
without having arrived at any conclusion would tend to lose interest and consequently
find it hard to continue the next time; this resulted in a decrease of
learning speed and achievement.
317 Unesco Pilot Project: Follow-Up and Adaptation in Argentina and Bolivia

(b) After a few classes fast learners were always far ahead of the rest of the class,
making it very difficult for the teacher to promote discussions among the students.
The apparent need for enrichment beyond the programmed materials themselves
could not be met at the time, due to the high costs involved in using television
programmes.
The problem of keeping the students alert and challenged was given serious
consideration by the group working at IMAF (University of C6rdoba) and as a
result the programmed materials were modified. The first unit was organized into
lessons short enough to be covered almost entirely during a regular laboratory
period of eighty minutes and to be completed as homework, thus providing for
individual differences in learning speed. Each student could study at his own pace
during the laboratory period and then use the homework materials to the extent
necessary to ensure that he was ready to participate in discussions or to start a
new lesson when the class next met.
Because very fast students could complete the lesson before the end of the
period, the need for additional material or optional activities to preventthem from
experiencing boredom was recognized. The optional unit developed by the
Unesco Pilot Project for the more interested students was more adequate as a takehome
unit because it was quite difficult to use if only a few minutes of class time
were available. New materials serving much the same enrichment purpose as television
programmes, which were not easy to use, were consequently prepared. It
was thought convenient to expand the multi-media approach. After each lesson
students were given open questions and problems requiring application of knowledge
and skills developed in the laboratory to real-life situations. They also
carried out open-ended experiments at home. This proved to be effective in
promoting fruitful discussions at the next class.
Laboratory practice during the trial period revealed the need to counterbalance
the convergence of the linear programme. The most effective device for
introducing divergence turned out to be open questions, particularly those involving
the need to perform experiments in order to test a hypothesis. These had to be
relatively simple at first and, above all, relevant to the students’ everyday life.
Such questions greatly assist students to grasp the relevance of the scientific
method, as a systematic way of gathering and handling information, to situations
outside the laboratory.
In spite of the fact that the kits are portable, students are not given the opportunity
to carry them home for further experimentation because they are used
by several classes. Consequently experiments requiring home-made materials
were designed.
To keep the brighter students challenged a number of optional problems and
questions were introduced in each lesson. Students could choose from these on
the basis of their individual interests and needs. Discussion groups provided
students with the opportunity to compare their findings with those made by
others, as well as to benefit from clarifying remarks made by the teacher.
This method of laboratory sessions followed by discussion periods was tried in
C6rdoba. It proved a success both with teachers and with students. The reason
31 8 Case Histories

319
for this success probably lies in the fact that these discussion periods enable
students to interpret new situations in the light of their newly acquired concepts.
They find this verbalization of concepts a confirmation of their own awareness of
facts. This is not surprising, for most students have been subjected to the traditional
approach in science teaching and their awareness of facts has usually been
measured by their ability to verbalize them.
It is pertinent to mention an experience the author has had in this respect in a
trial performed in Tegucigalpa, Honduras, in 1967, during a vacation course for
<strong>physics</strong> teachers sponsored by Unesco. The trial was made with volunteer
students. The group was made up on the one hand of bright students seeking to
learn new things and on the other of slow learners seeking to acquire some basic
skills. None had previous experience in <strong>physics</strong> or had worked in a laboratory.
Nor did they know of any other role for the teacher than the traditional one.
Students met daily for a three-hour session. Teachers led discussions to help
students clarify their ideas on experiments they had performed at home, or performed
demonstration experiments when students had difficulty in drawing conclusions.
All the students approved of. or rather were enthusiastic about, the new
role played by the teachers. As for the activities themselves, opinions differed.
The brighter students thought they had learned most from group work and from
the ensuing discussions, whereas the slower learners felt they had learned most
from the experiments they had performed in the laboratory following the instructions
contained in the programmed guide. It seems obvious that some students
profit from a highly structured learning situation such as that provided by the
programmed laboratory, while others do better under less guidance and with
more freedom of choice. This finding is consistent with the experimental work
done by G. 0. M. Leith (Leith, 1968) in which personality factors are related to
learning behaviour. He relates students’ degrees of anxiousness and introversion
to learning in structured and in non-structured learning situations. In this respect
we feel that the optional problems which complement the ‘Physics of Light’
course provide a much wider range of stimuli and opportunities, and recognize
individual differences in personality. Class discussions of problems also allow the
teacher to cater for individual differences in personality and play an important
role in favouring transfer of learning to novel situations and in motivating subsequent
learning.
The learning experience gained by the student through the use of the programmed
laboratory sequences is limited; he reaches concepts by generalizations
and discriminations among only a small number of stimuli. It seems unfair to
expect that the student wil apply newly acquired concepts and patterns of thought
to completely new situations unless he is encouraged to exercise this faculty.
Interestingly enough, tests show that the student’s transfer ability appears to be
related to this same ability in the teacher. In a programmed laboratory situation
students work individually most of the time. Discussions provide the natural
occasion for teachers to develop transfer abilities among their students.
Organization of classroom actioities. Students work in groups of two during programmed
laboratory periods of eighty minutes. From trials we learned that they
Unesco Pilot Project: Follow-Up and Adaptation in Argentina and Bolivia

prefer group work to individual work. When doubts arise, the students spontaneously
include other nearby groups in their discussions. The teacher becomes
involved only when his help is requested. During this time the teacher converses
individually with students interested in special problems or requiring additional
explanations.
Problems are given with each programmed lesson, so that those who complete
the lesson before the end of the class period can begin to work on the problems.
The last two minutes of the period are allotted to the students to put away their
equipment neatly in assigned places.
In spite of the fact that the correct answer to each frame of the programme is
written on the following page, to date no case of students copying the answers has
been registered. They accept the small challenge implied in responding by themselves.
Nor have there been difficulties with the care of the equipment or the completion
of the work outside class. Since the beginning of work on this programme,
total responsibility for learning has been transferred to the student. He has been
made to see that the teacher is simply offering him an opportunity to learn, and
that if he does not take advantage of it he deprives himself, and not the teacher or
the <strong>school</strong>.
In homework students finish the lesson, ifthey have not finished it in class, they
work on problems of their own choosing, they perform experiments with very
simple materials and they enter their data and opinions or conclusions on the
problem sheet.
In discussion periods (forty minutes each) the student brings his own paper with
as many solved problems as he likes and participates in discussions related to those
problems. Several group techniques are used for organizing discussions.
The teacher participates in discussions or performs experiments when required
by the class for clarifying ideas or arriving at a conclusion. Sometimes he shows a
film or introduces new problems. Tests are given to the students during discussion
periods. Most of them serve the purpose of self-evaluation and synthesis.
When the ‘Physics of Light’ course was tried in teachers’ seminars, most of
them seemed to be in favour of discussion periods but strangely enough many of
these same teachers do not allow time for discussions in their own classrooms.
Their reluctance to do so lies in their fear of being unable to answer all the questions
posed by students. This fear indicates allegiance, however unconscious it
may be, to an outdated conception of the role to be played by the teacher as a
depository of all information, available for use at any time.
A properly prepared teacher’s guide is a great boost to teachers’ morale and
can do much to encourage them to enter into discussion with students. The
guides prepared by the Unesco Pilot Project referred only to the use of film loops
and television programmes. A complete guide for teachers using the course is
needed and we plan to prepare such a guide in the near future.
A.5.4 Trials in Bolivian secondary <strong>school</strong>s
The Association for the Improvement of the <strong>Teaching</strong> of Physics in Cochabamba,
Bolivia, became interested in experimenting with the materials of the Unesco
320 Case Histories

Pilot Project, for which it gained the cooperation of the Bolivian Ministry of
Education, of Unesco and also of the Institute of Mathematics, Astronomy and
Physics in the University of Cordoba, Argentina.
The experience began with a seminar in which thirty-seven teachers familiarized
themselves for four weeks with the use of the programmed laboratory and the discussion
of problems and situations. More emphasis was placed on the attitudes
that teachers should assume with their students in using these methods than on
the content itself. The teachers found in the programmed laboratory a real opportunity
for changing their methods, even in those cases where the <strong>school</strong>s did not
have laboratories. (To improvise a laboratory it was necessary to get enough
tables to allow an area of 50 cm by 40 cm for each student and to instal a few
electrical outlets.)
During the seminar the group chose leaders in the different cities and each of
them was given a case with material. (An appropriate carrying case allowed the
teacher to take his equipment from one <strong>school</strong> to another, if this were necessary,
or to store it if there were no available cupboard space.)
It was made very clear during the seminar that if they wanted to make any
changes in the teaching programme, the teachers themselves would have to
assume the responsibility without waiting for outside help.
Within six months of the beginning of the experiment Professor Ferreyra, who
was one of the directors of the seminar, made a tour with the purpose of giving
guidance to the teachers and evaluating their progress. The following changes
were observed :
(a) The equipment and texts were being produced in Cochabamba, with the result
that the number of students participating in these trials increased from 1200 to
3332. (Originally 600 kitsand texts were brought from the University of Cordoba
to be used by 1200 students.)
(b) The teachers who had assumed the responsibility of conducting the trials had
been able to equip laboratories in their <strong>school</strong>s. (In Cochabamba the programmed
laboratory was used in twenty <strong>school</strong>s, of which only two had laboratories six
months before.)
(c) Other teachers who had not participated in the seminar had been incorporated
into the trials.
(d) Teachers had obtained from their communities or their <strong>school</strong>s the necessary
funds for texts, equipment and building adaptations.
(e) The teachers werevitally interested in continuing to use these methods to teach
other parts of the <strong>physics</strong> curriculum; they also reported having noted more
interest in the study of <strong>physics</strong> among their students.
(f) The materials were being used under the most varied conditions, among
which were: individual and group study outside <strong>school</strong>, use in courses of more
than fifty students with only one teacher, and simultaneous use in various <strong>school</strong>s
sharing the same equipment.
The success of the project may be attributed to the existence in Cochabamba of
321 Unesco Pilot Project: Follow-Up and Adaptation in Argentina and Bolivia

an association of <strong>physics</strong> teachers whose members feel that they have themselves
the responsibility of improving teaching and to the fact that the teachers saw in
these methods a real possibility, within their grasp, of enabling students to do
experimental work.
A.5.5 Feedback from teachers in Argentina and Boliuia
Seminars for <strong>physics</strong> teachers were held in different cities for discussing the multimedia
approach and as a result many teachers have become interested in trying
out the materials with their students. Experience shows that these seminars were
effective in motivating teachers to acquire the necessary re<strong>source</strong>s for implementing
the course from cooperating organizations or from the budgets of their own
<strong>school</strong>s.
Teachers using these materials have reported that they would like to have, and
that their students are asking for, similar programmed or structured experiments
for other areas of <strong>physics</strong>, but unfortunately such materials do not yet exist. This
suggests the advantage of producing a number of short programmed units on
basic topics that can be used in present <strong>physics</strong> courses. Unessential or complementary
topics could be dealt with in lectures by the teacher or by the students
themselves.
These short units, besides pointing out what is essential in the programmes,
would offer the possibility of a gradual change in teaching that would be more
easily accepted by the authorities and by the teachers themselves. Out of a number
of short units each teacher could build up a desired sequence, according to his
time limitations, his personal preferences and to the practical possibilities.
A.5.6 Conclusion
The hypotheses tested by the field trials of the combinations of methods, techniques
and materials produced by the Unesco Pilot Project seem to have been confirmed,
even though not all the possible media such as television and film loops
have been tried. The students have responded positively to this way of working. It
turns the study of <strong>physics</strong> into an experience of meaningful inquiry. The teachers
who have now used the ‘Physics of Light’course are enthusiastic and show adesire
to have similar material to teach other topics of <strong>physics</strong>.
The Unesco Pilot Project showed that, through international cooperation and
encouragement to centres interested in the improvement of teaching, it is possible
to produce materials of this type in Latin America. It is hoped more wil be done.
Extensive complete courses should not be produced, as they may be difficult to
apply, but production of a number of short units, flexible in their use, should be
encouraged.
Such units should be accompanied by teacher’s guides which give great importance
to the relations and connections between the various parts as well as to
the methods of thought and work characteristics of science.
The information gathered from teachers and students who have tried the course
322 Case Histories

supports the following view that the integrated multi-media approach is an
adequate method for introducing laboratory experiments as a fundamental tool
for learning <strong>physics</strong> under the conditions prevailing in Latin American <strong>school</strong>s.
This does not mean that this method is the only possibility or that it is superior to
other types of laboratory work; it is simply an effective approach for bringing
about changes in teaching.
The availability of simple and inexpensive equipment is not enough to produce
the desired changes; it is the attitude of the teachers that must alter and in this
respect this method has proved its merits. Those who have used it have overcome
their fear of the laboratory, gradually feeling more secure about it. It has helped
them to understand the objectives of the teaching of <strong>physics</strong> in secondary <strong>school</strong>s.
When this has been widely achieved, teachers wil be able to use laboratory
experiments of a more open type in their <strong>school</strong>s, which wil encourage a more
accurate approximation to real inquiry.
A.6
A.6.1
New Zealand adaptation of PSSC
N. E. Heath
Organization of education
Post-primary education in New Zealand begins at the age of twelve with Form 1
followed by Forms 2 to 7, reached at the age of eighteen. Until 1968 a five-subject
School-Certificate examination was taken at the end of the Form-5 year. An
examination qualifying for University Entrance was taken one year later. Pupils
could then stay at <strong>school</strong> for a further year after which good marks in the university-scholarship
examination would give exemption from first year studies in
some university courses.
For the past four years it has been possible to pass the School-Certificate
examination in a single subject and the university authorities are moving towards
an entrance examination two years after School Certificate.
A.6.2
The history of the change in science educalion
In 1961 representatives from universities and the Department of Education met
with science teachers to discuss the suitability of the American P S S C course for
introduction into New Zealand <strong>school</strong>s. It was agreed to run a pilot scheme in
selected <strong>school</strong>s. These <strong>school</strong>s were provided with all the necessary equipment,
films and texts, and the course was followed by a special University Entrance
<strong>physics</strong> examination paper for the pupils involved in the pilot scheme.
The course, tried in Form 6, was found to be too long for a one-year course.
Some material was considered suitable for work in Form 5 and a School-
Certificate <strong>physics</strong> course was devised incorporating some P S S C material with an
extra electricity section more suited to New Zealand needs. After trial and modification
the Form-5 course has proved to be a good introduction for Form-6
work and for those going to technical colleges. It wil continue to run as an
alternative to a traditional <strong>physics</strong> course until 1975.
323 New Zealand Adaptation of PSCC

Meanwhile trialsof new courses in biology and chemistry were being conducted
in Form 6.
By 1968 a combined-science course had been developedfor Forms 1 to 5, leading
to a single-subject pass in School Certificate. It is probable that by 1975 the choice
of separate subjects, <strong>physics</strong>, chemistry and biology, in the School Certificate wil
be replaced by the choice of physical science and biological science, or a singlesubject
science.
For Forms 6 and 7 groups organized by the universities have produced a twoyear
course, suitable for New Zealand requirements, no longer following P S S C,
though greatly influenced by it. This course is now fully operational.
A.6.3 Objectives in the science course
(1) A knowledge of basic facts, principles and theories.
(2) An understanding of fundamental concepts and their application to new
situations.
(3) The ability to identify a problem; to bring to bear earlier experiences relevant
to it; to formulate explanations and hypotheses; to test by experiment and other
means in order to accept, modify or reject; to draw conclusions.
(4)The development of skills appropriate to science: the ability to use scientific
apparatus accurately, to construct and interpret tables, charts and graphs, to find
relevant information from reference <strong>source</strong>s.
(5) The development of scientific attitudes such as open-mindedness, intellectual
honesty, a willingness to suspend judgement and a recognition of the tentative
nature of theories.
(6) A recognition of the importance of science in society.
(7) The development of a continuing interest in science.
A.6.4 Materials
Teacher’s guide material has been produced by science teachers and inspectors
working with the Department of Education’s curriculum development unit. A
selection of text<strong>books</strong> has been written by New Zealand teachers. P S S C-type
apparatus is available, and much use is made of P S S C films obtainable on free
loan from the National Film Library. Film strips, film loops and other visual aids
are being made available and a series of television programmes is under development.
A.6.5 Time allocation
For the science course for Forms 1 to 5 the time allocation is sixty periods a year
of forty minutes each in Forms 1 and 2; ninety periods a year in Forms 3 and 4;
one hundred and fifty periods a year in Form 5.
324 Case Histories

A.6.6 The content of the Form 1 to 5 course
The conceptual approach has been adopted as being most suitable for adaptation
to the needs of varying ability groups. Simple experiments and factual observations
are designed to develop a spirit of inquiry and so, with adequate guidance
from the teacher, to lead to the formation of a concept or generalization. This may
be tested on related phenomena and can suggest further lines of enquiry.
The concepts at this stage are elementary but once formed are readily available
for use. By the end of the fourth year the following basic concepts and themes
should have been absorbed:
(a) Nature of matter; its particle nature, structure and bonding.
(b) Energy; its transmission, conservation and transformation; matter-energy
relationships.
(c) Time, size and space; instruments as extensions of the senses.
(d) Diversity and orderliness.
(e) Dependence and adaptations.
(f) The evolution of living things through the ages.
(g) Equilibrium.
(h) The cell as the basis of life.
(i) Man and his attempts to control and modify his environment.
An appreciation of the natural unity of science as a study of man and his
environment wil arise from these ideas and this unity is maintained to the end of
the course.
The <strong>physics</strong> of the course in Forms 1 and 2 introduces ideas of time, distance
and astronomy; the particle nature of matter; force and energy; radiant energy;
electrical energy. In Forms 3 and 4 the syllabus is a continuation and development
of that for Forms 1 and 2. It has been written so that it forms a rounded-off course
for the sake of those who do not continue with science in Form 5.
Intellectual honesty, open-mindedness, a recognition of the tentative nature of
theories and the uncertainty of man’s knowledge are characteristic scientific attitudes
and should be established if the experimental work is conducted as a true
inquiry and not as a justification of preconceived conclusions. It is hoped that the
course for Forms 1 to 4 wil develop a continuing interest in science and a recognition
of the significance of science in society.
During the year in Form 5 Newton’s laws of motion are introduced. Energy
transmission is considered further, including the energy of waves. Energy in
electrical systems covers the energy of a charge in electric fields, electro-magnetic
induction and a study of alternating currents.
At the end of Form 5, the School-Certificate examination includes both objective
and essay-type questions.
325 New Zealand Adaptation of PSCC

A.6.7 Physics in Forms 6 and 7
From 1963 to 1969 a choice of PSSC-type or traditional <strong>physics</strong> was offered in
the University Entrance examination, but a single syllabus course came into
operation in 1970. The programme starts with scientific measurement and then
follows three lines of development: (a) the historical development of a theory:
planetary and satellite motion leading to the inverse-square law, (b) the development
of a theory: the conservation of energy, (c) investigation of the properties of
light, leading to a possible model. The unifying concept of fields, gravitational,
electric and magnetic, is introduced, leading eventually to a model of the atom
and on to the ideas of wave-particle duality. The scheme is shown in the chart
opposite. (The numbers refer to the topic numbers in the programme.)
Further details on the course are obtainable from the Science-Curriculum
Officer, Curriculum Development Unit, Department of Education, Wellington,
New Zealand.
326 Case Histories

<strong>Teaching</strong> schedule - U E Physics
Introduction. Scientific method -
(8 periods)
Basic mechanics in
two and three
dimensions
7. vectors (6 periods)
8. Forces (4 periods)
11. Projectiles
(4 periods)
12. Circular motion
(4 periods)
Deoelopment of n
theory (historical)
12. Moons, planets,
satellites leading to
inverse-square law of
gravitation
(4 periods)
Development of' U
model
15. A model oC a gas
and definition of
temperature
(9 periods)
principles of mechanics
6. Kinematics (10 periods)
12. Gravitational fields
3.
L
Derelopnient of the
concepts of n theory ~
conserticition of energy
principle
13. Conservation of
(i) Kinetic energy
(4 periods)
(ii) Mechanical
energy (6 periods)
14. Conservation of
mechanical energy
and heat (4 periods)
Other forms of energy
which we have found
useful to define so
that conservation of
energy remains true
(1 period)
Some experimental
facts about light
1. Reflection
(10 periods)
2. Refraction
t
A
A rnodelfor light
2. Particle model
(4 periods)
3. Waves (4 periods)
4. Wave model
(6 periods)
5. Interference ~ a
unique property of
waves and a test for
the wave model
( 10 periods)
A iiriq>ing coiicept ~ fields
12. Gravitational fields (I period)
16. 17, 18, 19. Electric fields (20 periods)
20, 21. Magnetic fields (8 periods)
A moclel oftlie atom
23. Rutherford atom
A modelfor the nucleus
25. A few facts ~ unfinished
24. Photoelectric effect (4 periods)
Wave -particle duality. IdeaofBohr theory
and its support by wave-particle duality
(4 periods)

B Details of Various Projects
In addition to the case histories included in the previous appendix it was felt that it
would be helpful to include some account of a number of additional projects recently
developed. This chapter does not attempt to be comprehensive, but it is hoped that the
information given about those included may be of interest to those concerned with
developing new programmes.
B. 1 Engineering Concepts Curriculum Project: The Man-Made World
During the spring of 1964, a group of engineers and high-<strong>school</strong> science teachers
held several meetings at Bell Telephone Laboratories in the United States of
America to consider the possibility of a high-<strong>school</strong> laboratory science course
based on engineering concepts.
The primary objective of the project was to contribute to the technological
literacy of young people. The 'target population consisted of those high-<strong>school</strong>
students planning some education beyond secondary <strong>school</strong>, and who were not
contemplating careers in science or engineering. It is this group which displays
aversion to mathematics and science courses, and among which is found the antitechnology
sentiment so eSident today. The course was designed to present to this
group of students a basic understanding of the characteristics, capabilities and
limitations of modern technology.
The material is intended for use in the last three years of high <strong>school</strong>, for boys
and girls aged 15-18 of average to above-average ability. It has also been used
successfully at the college freshman and sophomore level. No previous specific
experience in science is necessary, but a basic knowledge of arithmetic and
algebra is required.
About two hundred teachers have adopted the entire course. Approximately
seven thousand students have been involved, from 175 <strong>school</strong>s.
B. 1.1 Description of the course
Throughout the development of the text, one basic approach to the presentation
of concepts has remained unchanged. Early in the project the decision was made
to work from an actual problem to the solution framework and then to the concepts.
This is in strong contrast to much of science teaching, where the conceptual
material is presented first, often in abstract terms, and one works through the
328 Details of Various Projects

hierarchy of learning toward the ultimate goal of an illustrative application.
The Man-Made World represents a first step toward a multidiseiplinary educational
experience. From the beginning the course has fallen between science and
mathematics; in recent years it has involved an increasing content from the social
and behavioural sciences.
Man-machine interaction and the process of decision making through
modelling and optimization, using algorithms when possible, constitute the
major thrust of the course. Problems in this area range from analysing a graph of
gasoline consumption against speed to determining the most effective path for a
patrol car to cover a given police precinct. Urban problems such as air pollution,
solid waste disposal, traffic control and population growth provide the vehicle
with which the students learn to work on complex problems and attempt solutions
through systems analysis.
A brief look at the contents of the text reveals major topics such as: decision
making, algorithms, optimization, production planning, linear programming,
models, graphs, analog computers, signals, input-output prediction, symbols
and machines, logic circuits, binary numbers, memory circuits. flow charts, programming
languages, dynamic systems, amplification feedback, stability, control
of dynamic systems, etc.
A theme running through the course is the understanding tha there are many
possible solutions to complex social, economic and personal problems, and that
the forthright, simple, direct answer is often also wrong.
Modelling and the use of analogies form the basis for considerable study of
man-made devices and systems. There are more than fifteen laboratory experiments
in which the students solve problems on the analog computer. These
range from pipeline pressures to population projections. Simulation of the docking
of a boat or the linking of satellites in space is also a part of this laboratory
phase of the course. In contrast to the work with logic circuits the work with the
analog computer is done without any study of what goes on inside the computer,
but rather by looking at the analog computer as an input-output device, whose
only limitation is the imagination and creativity of the person using it.
The process of change and periodicity is studied through an intensive look at
sine waves and their characteristics.
The feedback process is studied from the standpoint of various human feedback
systems first. The use of feedback in social and electrical systems to eliminate
‘noise’ and to effect closer control is emphasized. We usethe boy-girl arguments
that are so familiar at this age as an example of how feedback can result in uncontrolled
oscillation.
By attempting to perform various ‘simple’ tasks while looking in a mirror the
students realize how much of what they do results from the development of
closed feedback loops, and that learning itself is really a matter of reinforcement
through proper feedback.
Extension of the concept of feedback leads to a study of amplification and
stability in some depth, again drawing from both social and personal problems
as well as from engineering devices and systems.
329 Engineering Concepts Curriculum Project: The Man-Made World

Computers are used in the course in different ways. First, the analog computer
is used to solve fairly simple algebraic problems. It is also used to simulate
physical situations that cannot readily be produced with real equipment in the
laboratory; for instance the simulation of the docking of a boat that continues
to ‘coast’ after the power is cut off, the simulation of falling bodies under various
conditions of gravitational pull, and environmental resistance and population
growth under varying conditions.
The digital computer is used as a mathematical machine and as a device for
modelling real systems. Problems that could not be solved easily without the highspeed
digital computer can be examined for their concept-building value without
involving the student in a mass of mathematical trivia. The mystery and fear of
the digital computer is allayed by the teaching of logic and logic circuits using a
very simple logic circuit board that the student can actually wire up to solve
simple problems such as the wolf, goat, cabbage problem or to demonstrate the
shift register or a binary adder. Through the use of a cardboard computer the
student can actually follow the path along which information flows in a digital
computer.
One of the objectives of The Man-Made World is to take the mystery out of the
computer while revealing its power as a modelling device and fantastically rapid
data processer. The students learn that man can and does communicate with
machines, and that the power of the computer rests on the ability of man to
devise logic circuits, develop devices to use these logic circuits, and invent
systems for using the devices more effectively.
B.1.2
Outline of the course
Chapter 1 Technology and man
1 The man-made world
2 Matching technology to the human user
3 A quantitative look at the yellow light problem
4 Preventive health care
5 Automated multiphasic health testing centres
6 Problems which appear in social systems.
Chapter 2 Decision making
1 The elemen,ts of decision making
2 Types of decisions
3 Algorithms
4 Algorithm for a decision problem
5 Criterion
6 Optimization with few alternatives
7 A more complex route-planning problem
8 Not all problems can be easily solved
9 Conclusion
330 Details of Various Projects

Chapter 3 Optimization
1 Introduction
2 Queueing problems
3 Probability
4 Queueing studies
5 Games
6 A production-planning problem
7 Graphing inequalities
8 A transportation-planning problem
9 Conclusion
Chapter 4 Modelling
1 The nature of models
2 The graph as a descriptive model
3 A descriptive model of traffic flow
4 Models for re<strong>source</strong> management
5 A population model
6 Exponential growth
7 An improved population model
8 Uses of models
Chapter 5 Systems
1 Introduction
2 Input-output ideas
3 Find the parts of a system
4 Rateinputs
5 Population model for a town
6 The noise-environment system
7 Measuring systems
8 The range of systems
Chapter 6 Patterns of change
1 The importance of change
2 Communication with language
3 Speech
4 Spectrograms for speech
5 Signals related to sinusoids
6 Not all signals are sinusoids
7 Interhuman communication
8 Conclusions
Chapter 7 Feedback
1 A feedback system
2 Goal seeking
3 Feedback as self-regulation
4 Feedback for disturbance control
5 Automatic compensation
6 A feedback example
7 Instability in feedback system
8 Final comments
331 Engineering Concepts Curriculum Project: The Man-Made World

Chapter 8 Stability
1 Introduction
2 Skyscrapers beget skyscrapers
3 Stability in traffic flow
4 The Black Death
5 Epidemic model
6 An improved epidemic model
7 Law of supply and demand
8 Instability in physical systems
9 Uses of instability
10 Summary
Chapter 9 Machines and systems for men
1 Introduction
2 Man as a controller
3 Man in communication
4 Man limited by environmental needs
5 Man and sensing
6 Prosthetics
7 Matching technology to man
8 Final comment
Chapter 10 The thinking man’s machine
1 The key to man’s survival
2 Man as a symbol maker
3 Ciphers and codes
4 Symbols and machines
5 Digital computers: What goes in and what comes out
6 Digital computers: What’s inside?
7 Past, present and future of the computer
Chapter 11 Communicating to computers
1 Introduction
2 Loops, loaders and bootstraps
3 Building blocks for programs: Subroutines
4 Programs for writing programs
5 Conclusion
Chapter 12 Logical thought and logic circuits
1 Introduction
2 How to make electriccircuitssay ‘ and ’ and ‘ or ’:
Introduction to logiccircuits
3 An example: The majority vote problem
4 How to make an electriccircuitsay ‘not’
5 Analysis U. synthesis
6 Additional thought on logical thought and circuit models
7 Summary and conclusion
332 Details of Various Projects

Chapter 13 Logic circuits as building blocks
1 Introduction
2 The decimal and the binary number systems
3 An automatic parallel
4 Numbers with sign
5 A circuit which compares the magnitudes of two numbers
6 A ‘ free ’ circuit
7 Conclusion
Chapter 14 Machine memory
1 Introduction
2 The basic relay memory element
3 An addressable memory
4 Shifting and shiftregisters
5 Circuits that count
6 Turning a number into action
7 Conclusion
Chapter 15 A minimicro computer
1 Introduction
2 Transferring binary information between components (copying)
3 Input, output and memory
4 Arithmetic unit
5 Instructional cycle and control unit
This project is under the direction of Dr E. E. David of Bell Telephone Laboratories and
Dr John G. Truxal and Dr E. J. Piel.both of the Polytechnic Institute of Brooklyn, 333
Jay Street, Brooklyn, New York 11201, USA.
The following materials are available: (1) Student text: The Man Made World; (2)
Laboratory Manual; (3) Teacher’s Manual; (4) Student Tests. They are published by
McGraw-Hill (Webster Division) and are obtainable from McGraw-Hill (UK), Maidenhead,
Berkshire. U K.
B.2 Harvard Project Physics
In 1964, the year that the project was formally organized, enrolment in high<strong>school</strong>
<strong>physics</strong> courses had reached its lowest percentage level in US history.
Despite the stimulus that Sputnik gave to efforts in the United States to improve
secondary-<strong>school</strong> science teaching, and despite the creation of new <strong>physics</strong>
courses an even larger percentage of high-<strong>school</strong> students were avoiding <strong>physics</strong>.
Since 1964 some two hundred physicists, scientists and scholars, teachers and
science educators, brought to Harvard from all parts of the United States, have
written, tested, and revised a new approach to teaching <strong>physics</strong>.
The course has been evaluated in <strong>school</strong>s all over the country and the results
prove that it works. Teachers and students are enthusiastic about it and, in most
classes where the course is offered, enrolment in <strong>physics</strong> has jumped dramatically.
With these test results, the Harvard team completed in 1969-70 the largescale
effort to help the rapidly growing number of <strong>school</strong>s that wish to introduce
the course under the title The Project Physics Course.
333 Harvard Project Physics

Harvard Project Physics has worked to create a course that could be adapted
in classroom use to appeal to a wide variety of students, from the potential
<strong>physics</strong> major to the possible dropout. The audience that the project has tried
hardest to reach is the large group of students who for one reason or another
avoid <strong>physics</strong> in high <strong>school</strong>. Since the early 1900s the percentage of students in
the United States taking high-<strong>school</strong> <strong>physics</strong> has steadily dropped, while enrolments
in biology, chemistry and mathematics have either held their own or
shown gains. In 1958 one student in four took <strong>physics</strong>; in 1965 the fraction was
down to less than one in five.
The future engineering or science major is not the only high-<strong>school</strong> student
who needs a good introduction to <strong>physics</strong>. Society is becoming ever more technical,
and in the 1970s those who hold even the simpler jobs in business and
industry wil find themselves handicapped without some knowledge of physical
science and of scientific thinking. For students who intend to major in the
humanities or the social sciences in college, high <strong>school</strong> may be the best, and for
many the only, time to gain an appreciation of science and the way it has deeply
influenced western culture and technological society.
The Project Physics Course is a solid introduction to the most enduring concepts
in <strong>physics</strong>, organized around six basic topics: the study of motion, planetary
dynamics, energy, waves and fields, structure of the atom, and the nucleus.
But the course stresses throughout the humanistic roots and consequences of
science. Interwoven with the ‘straight’ <strong>physics</strong> are such topics as the way physical
ideas have developed and influenced contemporary culture; the personality and
historical background of the men and women who made the key contributions;
the effect of <strong>physics</strong> on other sciences, especially astronomy and chemistry; and
the interplay between the growth of <strong>physics</strong>, developing technology and its consequences
for society. Since the course includes not only <strong>physics</strong> but material
from other natural sciences, as well as some topics in the humanities and the
social sciences, every student should find an entry to the course materials that is
both educationally and personally relevant.
B.2.1
A multimedia approach
The Harvard Project has pioneered in the developing technology of education,
assembling the first truly ‘multimedia’ system for understanding <strong>physics</strong>. Besides
the student texts and laboratory guides, the project has produced and tested
an impressive array of learning aids: 49 film-loops (super-8; colour), 6 anthologies
of relevant readings, 3 16 mm films,2 film strips, some 60 transparencies for
overhead projection, 10 programmed instruction booklets, 6 teacher guides and
re<strong>source</strong> <strong>books</strong>, 100 teacher demonstrations, 125 student activities and 55 items
of laboratory apparatus.
The variety of multimedia aids to learning is not intended simply to enrich the
text; they have been carefully integrated to complement and reinforce one
another, to present the various topics in <strong>physics</strong> in the most effective way possible.
Thus the text does not have to be the predominant <strong>source</strong> of input to the
334 Details of Various Projects

student. Some concepts in <strong>physics</strong> are more easily grasped by students when, for
example, they perform an experiment, or work with a film loop that takes up a
single topic, or follow the steps in a programmed instruction booklet.
Most of the hardware was created especially for the new course by the project
staff. For example, to simplify teaching and to save the <strong>school</strong>s money, the project
has developed simple, modular laboratory equipment which can be linked
in various combinations for different experiments. Since the same piece of equipment
often plays a part in a number of different experiments, the students gain
familiarity more quickly in the use of laboratory instruments.
Each of the 8 mm film loops presents a single concept in <strong>physics</strong>. Many loops
take advantage of high-speed photography to present phenomena ordinarily unobservable;
and some move out of the laboratory altogether, to demonstrate
basic concepts in an out-of-<strong>school</strong> setting familiar to any student. For example,
a film loop of boats moving on a river helps to teach vector addition, and a pole
vaulter illustrates conservation of energy. About half of the loops are quantitative:
that is. the student can make measurements directly from the image when
it is projected on graph paper.
The programmed instruction booklets serve two purposes : assisting less-able
students with concepts used in the course, and presenting material (e.g. force
vectors) that is more difficult to explain in a text.
The readers assembled for each of the units in the course are anthologies
containing articles, papers. and even poetry and excerpts from science fiction by
scientists and non-scientists both contemporary and historical. who have been
influenced by the growth of <strong>physics</strong>.
B.2.2
Supplernentmy iiriits
The basic course of six units is meant to occupy a class only six to eight months.
The project has already assembled several of the twenty planned supplementary
units. From these teachers may choose units to fill out the course in a way appropriate
to the specific interests of the class. These units deal with such topics as
elementary particles. the history of discoveries in <strong>physics</strong>, special relativity,
optics, bio<strong>physics</strong>, and science and literature.
The reason for this arsenal of material, much more than any one teacher is
likely to use in his own class, is to make the course flexible, and to accommodate
the wide range of interests, talent and experience among teachers and students.
From the beginning the project has sought the diversity that exists in reality and
has tried to design a course that encourages variation from class to class. From
the wealth of materials a teacher (or his student if the teacher wishes) can therefore
select up to one-third of the content for the year, in effect creating his own
<strong>physics</strong> course.
Some teachers wil prefer, for example. to emphasize a topic in the basic
course by assigning individual projects, additional readings, experiments and
film-loops, either to the whole class or just to those who show particular interest.
Others will choose to add one or more of the supplementary units, depending on
335 Harvard Project Physics

the inclination and level of the class. Some teachers prefer to give lecture-demonstrations
with the project materials; others let members of the class work together
in small groups to study the text, perform the experiments and so on,
providing help to the students only when called upon. Project materials encourage
a decentralized, non-authoritarian approach to teaching, which many younger
teachers prefer.
Whether in mathematical <strong>physics</strong>, in laboratory experiments or in reports on
historical readings, each student can demonstrate, with the aid of a variety of
project materials, his own achievement in his own way. The multimedia nature
of the course also accommodates differences in the way individuals learn. Those
who find any lecture or printed text difficult may more easily grasp the concepts
through a particular laboratory experiment or transparency. As Professor
Holton says, those who are deaf to <strong>physics</strong> may not be blind to <strong>physics</strong>.
At the end of each unit teachers are given a choice of four achievement tests
to administer: one wholly essay-type, one wholly multiple choice, and two which
mix essay and objective questions. The tests also vary in their emphasis on certain
kinds of skills and subject matter.
In short the Project Physics course shares one of the major preoccupations of
modern educational philosophy: the preservation and exploitation of individual
differences, both in teachers and in students, as a way to motivate the study of
subject matter.
Considerable interest has been shown in Project Physics in all parts of the
world. In helping foreign scientists and educators to introduce the course in their
own <strong>school</strong>s and teacher training institutes, Project Physics insists that the
material must not simply be translated but must be adapted. The directors feel
that to be most effective a foreign adaptation must take account of the local
history, culture, re<strong>source</strong>s and educational system. But they are convinced that,
just as the Project Physics Course successfully accommodates the variety of
students in American high <strong>school</strong>s, it can be adapted equally well to the diversity
of countries in the world, thus providing a humanistic science course of the kind
that modern citizens need perhaps as urgently as any other course in their
<strong>school</strong> years.
B.2.3
Organization of the project
From the beginning the direction of the project was shared by Professor Gerald Holton, Dr
James Rutherford and Professor Fletcher Watson. Nearly $5 million in supporting funds
were obtained from the National Science Foundation, the US Office of Education, the
Carnegie Corporation, the Sloan Foundation, the Ford Foundation, Harvard University,
and the'participating <strong>school</strong>s. In addition many people including Harvard faculty members
and a distinguished national advisory committee volunteered their services. The number
of project-trained teachers in participating try-out <strong>school</strong>s grew steadily and, in 1969-70,
over 20000 students in most parts of the country were taking the course in its last experimental
version, prior to publication by Holt, Rinehart & Winston in 1970.
The US version of the course materials can be obtained from the publishers, Holt,
Rinehart & Winston, Inc., 383 Madison Avenue, New York, NY 10017, USA. News-
336 Details of Various Projects

lettersand information about foreign adaptations may be obtained from Harvard Project
Physics, 316 Longfellow Hall, Harvard University, Cambridge, Mass., U SA.
The basic student text is in six units, each requiring four to six weeks’ time for coverage.
Unit Titles: Unit 1 ‘Concepts of Motion’; Unit 2 ‘Motion in the Heavens’; Unit 3 ‘The
Triumph of Mechanics’; Unit 4 ‘Light and Electromagnetism’; Unit 5 ‘Models of the
Atom’; Unit 6 ‘TheNucleus’. The Student Handbookcontains an abundance of laboratory
experiments, activities and film loop notes.
The readers (one for each of the six units) are collections of articles and book passages
on <strong>physics</strong>. A few are on historic events in science; others contain some particularly
memorable descriptions of what physicists do; still others deal with the philosophy of
science or with the impact of scientificthought on the imagination of the artist.
Test booklets (one for each of the six units, four tests in each booklet) include multiplechoice,
problem and essay-type questions, providing a variety of choices to the student to
demonstrate his achievement. Even within the tests, there are options to answer more
mathematically slanted or more philosophically slanted questions.
Programmed instruction booklets supplement portions of the course which some
students learn poorly by reading alone, vectors, for example.
Supplemental units deal with a wide variety of topics for students whose interestcarries
them beyond the basic core content.
The Teacher Guides (one for each of the six units) suggest organization for all the components,
outline the multimedia approach, and provide background materials, solutions,
references and re<strong>source</strong>s for continuing teacher improvement.
Laboratory materials and equipment, specially designed for the course, are produced by
Damon Corporation, and distributed by Holt, Rinehart & Winston. Transparencies (one
set for each of six units) are bound together with notes in the flexible and convenient Visubook
form. Film loops (super 8; colour) prepared by Project Physics at the National Film
Board of Canada and manufactured by Ealing Corporation are available for distribution
by Holt, Rinehart &Winston. Three 16 mm sound films,People andparticles, Synchrotron,
and The World of Enrico Fermi are available on both a rental and purchase basis from Holt,
Rinehart & Winston. Teacher training films are designed to help implement the approach
that distinguishes the Project Physics course from previous ones: a multimedia, multilevel,
humanistically oriented <strong>physics</strong> course with teacher and student choice to provide the
optimum student-teacher interaction.
B.3 Introduction to Natural Science: The INS project
This was originally planned as a college course but has been effectively used in
the eleventh and twelfth grades of American high <strong>school</strong>s.
The initial objectives were to develop a course which would be suitable and
attractive for the vast numbers of college students who dislike or fear science and
who especially avoid <strong>physics</strong>. For such students it seemed clear that the new
course had to be conceptual rather than addressed to development of skill for
problem solving. It had to integrate physical and life sciences as far as possible,
be somewhat philosophical and historical, and clearly relevant to the student’s
personal. social and professional interests. A two-year sequence was found to be
necessary for the purpose. The initial objectives have been met, and in the process
it has become clear that the approach and contents are also well suited for
the preparation of science majors as well.
337 Introduction to Natural Science: The I N S Project

To permit effective teaching (by people who are usually prepared as teachers
of physical science or of biological science) the course and texts were divided
into Part I ‘The Physical Sciences’, and Part I1 ‘The Life Sciences’, without
altogether losing integration between them. In general a physicist is well prepared
to teach Part I and a biologist or biochemist to teach Part 11. However, it is felt
that the primary requirement in the teaching is a desire to teach a course of this
broad conceptual character rather than any specific professional preparation.
The Teacher’s Guide offers detailed suggestions for the presentation of each
chapter.
The course, comprising Parts I or I1 or both, was being taught during 1969-70
to 1 lth and 12th year students (ages 16 to 19 years) at 7 high <strong>school</strong>s and at about
43 colleges of various kinds. The students at the high <strong>school</strong>s were expected to be
science majors for the most part, while the majority of college students were in
the non-science category.
For study of Part I ‘The Physical Sciences’, at least a year of algebra is required,
and some trigonometry must have been studied or be taught as part of
the course. Part I1 ‘The Life Sciences’ follows directly. (When Part I1 is taught
without Part I there must be some preparation through conventional <strong>physics</strong>
courses that include some atomic science.) The texts present the more difficult
portions (usually the more mathematical) in coloured type as optional material
that can be left out as required, following suggestions in the Teacher’s Guide.
The details of the content of the INS course are included in Chapter 8 of this
volume on pages 1 16-21.
This integrated science course was developed through the project called Science Courses
for Baccalaureate Education, under the direction of Dr V. Lawrence Parsegian, Chair of
Rensselaer Professor, Rensselaer Polytechnic Institute, Troy, New York 12180, U SA.
The following are available from Academic Press Inc., 11 1 Fifth Avenue, New York.
10003, USA: (1) Part I The Physical Sciences, by V. L. Parsegian, A. S. Meltzer, A. S.
Luchins, and K. S. Kinerson, 1968; (2) Part I1 The Life Sciences, by V. L. Parsegian, F. V.
Monaghan, P. R. Shilling, and A. S. Luchins, 1970; (3) A Teacher’s Guide is available for
each part; (4)A Laboratory And Mathematics Supplement.
Laboratory manuals offer 16 experiments for Part I and 19 for Part 11, from which the
teachers may select about half. The suggested apparatus is of simple design such as is
used for PS S C or equivalent secondary <strong>school</strong> <strong>physics</strong> teaching.
Each part has its own guide which provides fairly detailed suggestions for presenting the
chapters differently from the text treatment. There are listings of films,references for
additional reading, precautions, suggestions for time schedules etc.
B.4 Novosibirsk Project
A high <strong>school</strong> specializing in mathematics and physical sciences (Phys-Math
School, P M S) of the Novosibirsk University has been functioning for seven
years. Studying in it are some 450-500 students showing interest in, and ability
for, <strong>physics</strong>, mathematics and chemistry. The <strong>school</strong> provides its students with
secondary education in conformity with the general standards of USSR. The
338 Details of Various Projects

B.4.1
B.4.2
B.4.3
teaching goal at the P M S is to develop the abilities of the most gifted children and
train them for the further creative activities, primarily in the fields of natural
sciences.
Courses available
There are three courses at the PM S, differing in duration: three-year, two-year
and one-year, i.e. students are accepted after the seventh, eighth and ninth grades
of traditional high <strong>school</strong> respectively, their ages range from fourteen to sixteen.
Selection
Selection of pupils for the PMS is carried out in three stages. First a special
written test is given at general educational <strong>school</strong>s. These tests (called here the
first round of the Physical-Mathematical Olympiad for Schoolchildren) are
carried out by <strong>school</strong> teachers. Then in the district centres of Siberia, the Far East
and Central Asian Republics scientists of the Siberian Department of the USSR
Academy of Sciences and the faculty staff of the Novosibirsk University with the
help of local educational bodies carry out the second stage of selection. Here
written tests and colloquia are arranged in one of the contest subjects (mathematics,
<strong>physics</strong> or chemistry). In recent years some ten to twelve thousand
students have taken part in the second round of the Olympiad. About six hundred
of these are brought to attend a twenty-four day summer <strong>school</strong> in <strong>physics</strong> and
mathematics. The summer <strong>school</strong> operates each year from 1 August in Akademgorodok
(the Academy campus near Novosibirsk). Lessons and examinations
provide for an evaluation of the knowledge and ability of the participants of the
summer <strong>school</strong> and those finally selected are admitted into the Phys-Math
School of the Novosibirsk University.
Orgunizatioii of the cLirriculuin
The two-year course is considered to be the principal one, and further details wil
refer mainly to it.
The academic year is planned as follows :
1. Autumn term: 1 September to 18 December.
2. Winter examinations: 18 December to 28 December.
3. Winter holidays: 28 December to 21 January.
4. Spring term: 21 January to 25 May.
5. Spring examinations: 25 May to 7 June (in the first year of study) and 26 June
(in the graduating year).
Lectures are given to joint sessions of students of several parallel classes. Contact
hours (in mathematics, <strong>physics</strong>, chemistry and biology) are held in smaller groups
of twelve to fifteen students in classes and laboratories. Compulsory subjects
make up thirty hours weekly, students attending <strong>school</strong> five days a week (traditional
<strong>school</strong>s work for six days a week). An extra free day is meant for optional
courses and laboratory work selected by pupils themselves. Graduating classes
specialize during the spring term, having a full day for special courses and attend-
339 Novosibirsk Project

ing laboratories at the Research Institutes of the Siberian Department of the
USSR Academy of Sciences, where they either work according to the programme
designed for them or take part in some experiments carried out by the
research laboratories.
In Table 11 is the two-year course curriculum in <strong>physics</strong> in periods per week.
Table 11
First year of study
Graduating class
Autumn Spring Autumn Spring
semester semester semester semester
Lectures 2
Contact hours 4
Laboratory work -
Radio- and
photo-classes 2
Optional courses* 4
Special coursest -
2
4
3
2 2
5 4
-
3
- -
4 4
-
4
* Optional courses chosen by pupils according to their wishes and abilities.
t Compulsory only for those who decided to specialize in <strong>physics</strong>.
Besides lectures, contact hours (where students solve problems) and laboratory
classes, pupils get a.semester assignment of forty to fifty problems referring to the
basic parts of the course. Some of them are considerably more difficult than everyday
problems solved during contact hours and require of the student intense work
on his own as well as discussions with his classmates. The pupil may consult with
his teacher and has to report to him on his results three to four times during the
semester. Written tests are given twice in each semester, and during the winter and
spring examination sessions pupils take two examinations in <strong>physics</strong> (oral and
written).
Among those working part-time at the P M S there are many fullprofessors and
taught by five doctors and full professors and fifteen scientists from the Siberian
faculty members of the university as well as scientists from the Research Institutes
of the Siberian Department of the Academy of Sciences. In 1969-70 <strong>physics</strong> was
taught by five doctors and full professors and fifteen scientists from the Siberian
Department of the Academy of Sciences; six highly qualified teachers, members
of the teaching staff, worked together with them.
B.4.4
Structure and content of the course in <strong>physics</strong>
The general content and arrangement of the course in <strong>physics</strong> at the P M S corresponds
to the compulsory curriculum for senior grades of the USSR high
<strong>school</strong>s. The main peculiarities of the course are:
340 Details of Various Projects

(a) A number of additional, more complicated and interesting problems.
(b) A more profound and detailed treatment of the basic physical laws and
phenomena.
(c) A closer connection with modern <strong>physics</strong>.
(d) A detailed treatment of fundamental experiments, determining the basic
concepts of modern <strong>physics</strong>.
(e) A great number of examples from applied <strong>physics</strong> and everyday life like those
in Perelman’s Entertaining Physics.
(f) A wide application of algebraic and trigonometric calculations, including
vector diagrams and complex numbers, including the exponential form.
(8) Application of the elements of differential and integral calculus.
The study material in <strong>physics</strong> is graded for three levels. The first and principal
level includes the most fundamental concepts and laws, thus comprising the basis
for any further study of <strong>physics</strong>.
The second level includes additional, and to a great extent factual, material
meant for treatment and assimilation during the semester. Its aim is to give a
concrete and varied illustration of the basic principles of <strong>physics</strong>.
The third level includes optional material, interesting for the students but not
meant for assimilation. It is not included in the examination programme.
The content of the course in <strong>physics</strong> may differ depending upon the lecturer,
teachers and the average level of the students. Given at the end of this paper is a
list of the main topics for the two-year course arranged in accordance with the
three levels mentioned above (for grades 9 and 10). This list is adopted by the
curriculum committee of the PMS Science Council. and is the basis of the
curriculum.
B.4.5 Some comments on the course
Mechanics. Speciai attention is given to the understanding of the nature of forces
and their detailed analysis in a given experimental situation. In this connection
the difference between inertial and non-inertial frames of reference is stressed as
well as the special nature of pseudo forces in non-inertial frames. Special attention
is given to the laws of energy, momentum and angular momentum conservation
and to their wide application in solving problems.
Molecular <strong>physics</strong>. The development of a clear molecular-kinetic picture of
microscopic processes is specially stressed. Special attention is given to the second
law of thermodynamics and to the statistical concept of entropy. An idea of
Maxwell-Boltzmann distribution is presented.
The simple presentation of transport phenomena in gases, including estimates
of kinetic coefficients, is given. Hydrodynamics is presented as an application of
general laws of conservation to the continuous medium.
341 Novosibirsk Project

Electromagnetism. Attention is paid to the development of the ‘visual’(‘ tangible ’)
picture of the electromagnetic field as one of the forms of matter. In particular,
attention is given to energy and pressure of the field. Simultaneously, basic ideas
of the special theory of relativity are presented. At the end of this part Maxwell’s
equations are formulated in the integral form, and emission and propagation of
electromagnetic waves are considered. As applications both d.c. and a.c. circuits
are given, as well as the calculation of inductance and capacitance in the simplest
cases. In this and the next sections the Gaussian system of units is used, as a rule.
Oscillations, waves, optics. Resonance in mechanical as well as in electrical systems
is considered. In wave processes stress is laid on interference and diffraction, the
latter being considered on the base of Huygens’s principle. An essential new item
of the curriculum is the uncertainty relations for a wave packet as a first step to
understanding of the uncertainty principle in quantum mechanics. Relatively less
time is devoted to geometrical optics.
The atom and the nucleus. The principal concepts of quantum mechanics and their
applications to atomic and nuclear phenomena are given. Attention is first drawn
to the wave properties of particles (electron diffraction) and the quantum properties
of radiation (photoelectric effect). Then an idea of the uncertainty principle
and Pauli principle as the basis of all quantum-mechanical phenomena is given.
The general level of the course in <strong>physics</strong> surpasses that of J. Orear’s course
(Orear, 1967) and in some sections (thermal phenomena, geometrical optics,
interference and diffraction) it corresponds to the level of the course of R. Feynman
(Feynman, Leighton and Sands, 1964).
B.4.6 Laboratory work
Designed for the students are forty laboratory assignments which they are to
carry out individually and on their own. Some of them deserve mention : measurement
of forces in the Maxwell’s pendulum movement; determination of free-fall
acceleration by a turning pendulum; measurement of moments of inertia on a
torsion pendulum and Oberbek’s pendulum; determination of Young’s modulus
from elongation and bending; measurement of collision time of solid bodies and
propagation of elastic waves in them; determination of the coefficient of viscosity
for liquids ; measurement of heat conductivity for gases; determination of surface
tension by the measurement of the propagation velocity and the length of capillary
waves; current in the vacuum diode and the Richardson’s law; determination of
specific electronic charge by the magnetron method; Ohm’s law for alternating
current circuits; study of free and forced oscillations in the electrical circuit;
resonant phenomena; bridge and compensation methods of measurements ;
interference of light and wavelength measurement (Fresnel’s biprism and Newton’s
rings); rotation of the polarization plane in an optically reactive solution;
spectrum of emission of a mercury discharge lamp; photometry; study of a
microscope, and so on.
342 Details of Various Projects

B.4.7 Typical problems of average difficulty from various parts of the course
Find the minimum distance at which one proton can approach another. The
relative speed and the impact parameter are known.
A flat stream of an ideal incompressible liquid runs at an angle of 8 upon a hard
wall and breaks into two streams flowing along the wall in opposite directions.
Determine how thick the streams are ifthe initial thickness of the stream is known.
Draw a qualitative diagram of pressure distribution upon the wall; estimate the
maximum pressure and the width of the high-pressure zone.
Suggest a method for measurement of the mass of hydrogen, copper and uranium
atoms.
Two bodies have constant heat capacities C, and C2. Find the maximum work
which can be obtained, if they are used as a heater and a refrigerator in a thermal
machine, initial temperatures of bodies being T, and T2 respectively.
A conducting ring with a radius a, mass m and resistance R hangs vertically on an
elastic thread. Investigate free torsion oscillations of the ring in the magnetic field
H, perpendicular to the thread and parallel to the plane of the ring in equilibrium.
Estimate the lifetime of the Rutherford atom, if the initial radius of the orbit is
cm.
How does the brightness of the image of a star seen in a telescope depend on its
diameter and the focal length ?
Table 12
1. Mechanics
1
Profound assimilation
necessary
2
To be tested at the
semester examination
3
To be given if
desires
lecturer
1. Concepts of velocity
and acceleration
2. Relativity principle of
Galileo
3. Newton’s laws, types
of forces, detailed
analysis of forces
4. The gravitation law
5. Conservation laws of
energy, linear and
angular momenta
6. Work, potential, power
7. Equilibrium conditions
8. The moment of force,
angular momentum
1. Vector of angular
velocity
2. Friction
3. Elastic and inelastic
collisions
4. Derivations of
conservation laws
5. Non-inertial frames of
reference
6. The motion of charged
particles in an electromagnetic
field
7. The moment of inertia
1. The motion of solids
2. Coriolis force
3. Scattering to small
angles, cross-section,
Rutherford’s
experiment
343 Novosibirsk Project

Table 12 -continued
2. Molecular <strong>physics</strong>
1 2 ' 3
1. The concepts of
temperature and
thermal equilibrium
2. Internal energy and the
first law of
thermodynamics
3. Equation of state
4. The second law of
thermodynamics ;
efficiency of Carnot
cycle
5. An idea of molecularenergy
distribution
function
6. Pascal and Archimedes
laws
7. An idea of free-path
length and transport
processes
8. An idea of phase
transition
9. An idea of entropy (in
statistical <strong>physics</strong>)
1. Gas pressure U.
temperature ;
derivation of formula
2. Graphs of gas work;
is0 baric and
adiabatic curves
3. The possibility of the
equations of state
other than PV = RT
4. An idea of entropy in
thermodynamics
5. The thermodynamical
standpoint on heat
processes
6. Estimate of kinetic
coefficients
7. He'at capacity of the
ideal polyatomic gas
8. Surface phenomena
9. Bernoulli's equation,
lifting force
10. Solids, Hooke's law
1. Van der Waal's
equation of state
2. Derivation of
Maxwell distribution
3. The features of
Boltzman
distribution
4. Curves of phase
transitions
5. Electrons in metal
6. Heat capacity of
solids
7. Dilute gas
8. Plasma

~
Table 12 -continued
3. Electromagnetism
1 2 3
1. Charge, electrical field
2. Gauss’s theorem,
dipoles
3. Conductor in
electrical field
4. Capacity
5. An idea of energy
and pressure of
electrical field
6. Direct current;
charge conservation
law
7. Magnetic field of
current and its
interaction with
current
8. Magnetic dipole
9. Huygens’s principle
induction
10. Ohm’s and Joule’s
laws, Kirchoff’s rules
1 1. Self-induction
coefficient
12. Various devices,
motors, generators;
principles of operation
1. Derivation of Gauss’s
theorem and its
application to field
calculations
2. Field lines
3. Physical meaning of
E, D ; polarization
4. Density of field energy
5. Electrolysis; current
in electrolytes
6. Ideas of generators
of current and of
motors
I. Biot-Savart’s law
8. Physical meaning of
B, H; magnetization
9. Maxwell’s equations
in integral form
10. Dia-, para- and
ferro-magnetics
11. Instrumentation
12. Electrical circuits
with induction coils
and capacitors,
complex resistivity
13. General principles of
semiconductor radio
techniques
14. Principal ideas of
special relativity
1. Earnshaw’s theorem
2. t law
3. Current generators
in detail
4. Dependence of D on
E
5. Dependence of B on
H
6. Current in gases
I. Connection between
SI and Gaussian
system of units
8. Ideas of general
relativity

Table 12 - continued
4. Oscillations, waves, optics
1 2 3
1. Amplitude, frequency,
phase
2. Wavelength and wave
velocity
3. Resonance
4. Reflection and
refraction of waves
5. An idea of
interference and
diffraction of waves
6. Doppler effect
7. Refractive index
8. Lenses, construction
of images
9. Huygens’s principle
10. Scale of electromagnetic
waves
1 1. Dispersion of light
1. Oscillations under
friction
2. Plane and spherical
waves
3. Polarization
4. Amplitude
modulation, beating
5. Uncertainty relations
6. Group and phase
velocity
7. Thin-lens formula,
derivation
8. Interference and
diffraction, limit of
geometrical optics
9. Standing waves
10. Transmission of
energy by a wave
1 1. Emission of
electromagnetic waves
1. Fermat’s principle
2. Phase shift
3. Propagation of
sound
4. Non-equilibrium
emission
5. Laser
6. Holography
5. The atom, the nucleus
1 2 3
1. Uncertainty relations 1. Contradictions in 1. Mossbauer effect
2. Hydrogen atom. classical models of 2. Superfluidity and
Discrete spectrum atom superconductivity
3. Quantum numbers. 2. Diffraction of electron 3. Accelerators,
Pauli principle 3. Penetration through a colliding
4. Chemical bond potential wall
5. Photoelectric effect
6. Radioactivity
4. Quantization of atomic
angular momentum
5. Solids. Electronic
Fermi-gas
6. Semiconductors, diode
and transistor
7. Types of radioactivity
8. Nuclear reactors
9. Elementary particles

B.5 Nuffield 0-Level Physics Project
The Nuffield Ordinary Level <strong>physics</strong> project was one of the first science teaching
projects published in the United Kingdom under the auspices of the Nuffield
Foundation. The course is a five-year one for pupils from ages 11 to 16. It is intended
for the top 25 per cent of the academic ability range, in other words for
those pupils who wil be taking the General Certificate of Education at Ordinary
Level at the age of 16.
The project was initiatedby the late Donald McGill and brought to completion by Eric
Rogers with John Lewis and Ted Wenham as associate organizers.
The published material, obtainable from Longman, Harlow, Essex, UK, and from
Penguin Books Ltd, Harmondsworth, Middlesex, U K, consists of: (1) Teachers’ Guide:
in five volumes, Years I-V; (2) Guide to Experiments: in five volumes, Years I-V; (3)
Question Books (forpupils) : in fivevolumes, Years I-V; (4) Guide to Apparatus: a guide for
for teachers; (5) Tests and Examinations: a guide for teachers.
The apparatus for the course is available from Philip Harris Ltd, Ludgate Hill,Birmingham
3, UK, and other suppliers. Films for teachers. illustrating much of the experimental
work in the course, are obtainable from Public Affairs Department, Esso Petroleum,
Victoria Street, London, SW 1, UK. Special Nuffield 0-level examination papers, set by
the Oxford and Cambridge Examination Board on behalf of all the English examination
boards, are obtainable from the Oxford and Cambridge Examination Board, 10 Trumpington
Street, Cambridge, U K.
B.6 Nuffield Combined Science Project
The first of the Nuffield Science <strong>Teaching</strong> Projects to be published were the 0-
level projects in <strong>physics</strong>, chemistry and biology respectively, intended for children
aged 11-16 years in the top 25 per cent of the ability range. The need was felt
for a combined science project for the first two years of the 0-level course which
recaptured the unity of outlook and consistency of method which belong to the
whole of science.
The Combined Science Project is intended primarily for children of about 11-
13 years in age, but it is not confined to those of average or above average ability:
it is adaptable to the whole range of ability.
One of the Nuffield Foundation’s original terms of reference was that the subject
matter of Combined Science should be based on the material that had been
developed by the separate 0-level projects in <strong>physics</strong>, chemistry and biology. So,
following a careful analysis for content, philosophy and experimental approach,
ten topics (see below) were chosen to link together the material of the separate
courses and to unify as far as possible the differing viewpoints and approaches
which existed therein. It was of course inevitable that in this process some of the
flows and sequences of work as envisaged in the original schemes would have to
be modified to fit in with an overall view of science.
Trials were conducted with children of the full range of ability in <strong>school</strong>s of
all different types. They involved 80 teachers and 3000 children in 30 <strong>school</strong>s.
347 Nuffield Combined Science Project

B.6.1
Aims of the course
It was accepted from the outset that the unification and reconciliation of the wide
range of subject matter would be achieved by one teacher dealing with one class
in one laboratory, even though the specialist teacher might initially feel uncertain
about his competence outside his own discipline.
Combined Science stands in its own right, complete in itself but adaptable to
lead into any subsequent science courses including (i) separate Nuffield 0-level
courses in science, (ii) non-Nuffield 0-level courses in science, (iii) Nuffield
Secondary Science, (iv) C S E (Certificate of Secondary Education) work, (v)
project work in science. For this reason a realistic time allocation is vital and a
target of five forty-minute periods per week was set in developing the work.
It was considered to be of paramount importance that children should be
actively engaged in working (which includes thinking) in the laboratory, gaining
as much as possible of first-hand experience of science as a method of inquiry. In
this way children would (a) be developing an appreciation that hypotheses could
be formulated, tested and modified and (b) be given sufficient time and data for
the development of concepts.
Combined Science is, however, an introduction to science, a ‘first look’ at
phenomena and their interpretation. Children should be encouraged at all times
to try to appreciate that they have not reached an end point, that the final answer
has not been obtained purely on the results of one or two experiments, that there
may still be unsuspected factors to take into account, that the future is still wide
open, and that science has not provided the final word on the subject. Equally,
however, the fact that science is rooted in the world around us is not neglected,
and full opportunity has been taken to use children’s first hand experience as a
starter to the work in the laboratory.
The general aim has been to produce a <strong>source</strong> of ideas, material and comment
to allow teachers to devise their own cour+es. Particular attention has been paid
to extending children’s work outside the laboratory and it is hoped that the
suggestions made wil form the basis of many rewarding investigations.
To help in this aim a detailed Teachers’ Guide in three parts has been prepared,
giving explicit lists of requirements and procedures for carrying out experiments.
These are accompanied by teaching notes which by suggesting definite examples
exemplify the philosophy underlying the course and give some guidance on the
depth of treatment. It is not intended that such notes should be taken as a rigid
script which teachers must follow. It is further hoped that, once teachers have
gained experience with Combined Science and assessed the approach suggested
in the Teachers’ Guide, they wil modify, extend and innovate.
348 Details of Various Projects

B.6.2
Content
The ten sections are divided into subsections as follows:
One - The world around US
1 The exhibition - livingand never lived
2 Variety of things and grouping
3 Temperature
4 Estimating and measuring
5 Looking more closely at things
6 Earthworms
7 Making stuffpurer
Two - Looking for patterns
1 Movement and forces
2 Heating substances
3 Patterns of growth
Three ~ How living things begin
1 How do living things begin?
2 How do animals breed in water?
3 Breeding in mammals
4 How plants reproduce and make seeds
Four ~ Air
1 Air is all around us - effects
2 Difference between air and nothing
3 What is in the air?
4 Pressure
Five ~ Electricity
1 Circuit board work
2 Do all substances allow electricity to flow?
3 Trying to find out about electricity
Six ~ Water
1 Water from different places
2 Finding out about water
3 Animals and plants in water and on land
4 What is water?
5 Can electricity pass through water?
Seven ~ Small things
1 How small are small things?
2 Microbes
3 Particles
349 hluffield Combined Science Project

Eight - Earth
1 Products of the Earth
2 Soil
3 Development and growth of eggs and seeds
4 Crudeoil
5 Metals from rocks
6 Looking for differences between metals and non-metals
7 Investigation of ores
8 Substances from the sea
Nine - Insects
1 Locusts
2 Large white butterflies
3 Looking at other insects
Ten - Energy
1 Investigating the meaning of energy
2 Heat radiation
3 Light
4 Sound
This project, sponsored by the Nuffield Foundation, was originally planned in 196546
under the direction of M. J. Elwell and C. D. Bingham, both of whom were prominent
members of the Nuffield 0-level Project teams, in <strong>physics</strong> and biology respectively. The
second phase of the project (1966-69), consisting of development work, <strong>school</strong> trials and
preparation for final publication, was organized by M. J. Elwell, City of Birmingham
College of Education, Westbourne Road, Birmingham 15, U K.
Teachers’ Guides I and I1 contain material for the ten sections of work into which the
course is divided. Material for children has been prepared in the form of activitiesbooklets,
one for each section. They are not intended to be used as text<strong>books</strong>. Activities can be used
to start children thinking about a new piece of work, to give them ideas of things to do or
find out, to extend work done in the laboratory, to give some background to a piece of
work, to take the place of class discussion, to give practical instructions both for homeand
laboratory-based experiments, and to give visual stimulation and reinforcement.
Teachers’ Guide 111 contains details on apparatus, collected references to <strong>books</strong>, films and
film loops, and a mathematics appendix. The Combined Science texts are published by
Longman, Harlow, UK and Penguin Books Ltd, Harmondsworth, Middlesex, UK.
Nineteen film loops (in standard and super-8) are being produced.
The apparatus requirements for Combined Science are based on those of the separate
0-level Nuffield projects in biology, chemistry and <strong>physics</strong>, but there are modifications in
detail. Apparatus already bought for the separate subjects wil be suitable for direct use in
Combined Science in the majority of cases or with suitable modification to procedures in
the remainder. Wherever possible, children are encouraged to make and test their own suggestions
for carrying out an investigation into a topic; this procedure requires ready access
to apparatus which should, if at all possible, be stored in the laboratory itself
350 Details of Various Projects

B.7 Nuffield Secondary Science Project
The project is concerned with providing science teaching material for boys and
girls aged 13 to 16, who are unlikely to take the General Certificate of Education
0-level examinations in science. The material does not constitute a course, but a
<strong>source</strong> from which teachers may select and produce courses appropriate for their
own pupils. For this reason the material is flexible and capable of adaptation for
pupils over a wide range of ability and interests.
B.7.1
B.1.2
Project history
The team started work in September 1965 and in the first term of 1966 a smallscale
feasibility trial was conducted in 15 <strong>school</strong>s to find out whether samples of
the material were appropriate for the pupils and whether the teachers were
being given the help they needed. Full-scale development trials in 53 <strong>school</strong>s
started in September 1967. In the following year 212 <strong>school</strong>s in England, Wales
and Northern Ireland were involved, and the number grew to 258 in 1969-70.
After taking part in trials of prescribed ‘routes’ for one year, trial teachers
chose their own ‘routes’ for the following years so that over 200 different ‘routes’
were being used in the third year of trials. Schools have presented pupils for the
C S E (Certificate of Secondary Education) examinations. The material was published
in the summer of 1971.
Aims of the course
The criterion is that the work should have significance for the pupils. Significance
can be considered at a number of different levels, from that of immediate interest
to that of an understanding, however slight, of some of the problems of the
twentieth and twenty-first centuries; for example, those of energy, re<strong>source</strong>s,
world food supply or expanding population. Where significance is not immediately
obvious, the teacher needs to keep the objective very clearly in mind
if understanding of the work is to emerge.
Concepts can have significance in certain contexts and not in others. Space
travel, for example, has given ‘weightlessness’ a significance which it did not have
for most boys and girls twenty years ago. Similarly the level of significance may
often vary with the ability and maturity of the pupils, and the teacher needs to be
sensitive to this.
Considerable emphasis has been given to the involvement of the pupils
through their own experimental investigations of problems which are real to
them; such investigations constitute the major part of the work. These boys and
girls wil not become scientists but can, to a limited extent, be given some
feeling through their own direct experience of a few of the ways in which scientists
work. It is hoped, too, that they wil develop an attitude to science which
shows some understanding of what science is and how their own lives can be
affected by the use and misuse of scientific ideas. Since there are dangers of frus-
351 Nuffield Secondary Science Project

tration if the work is too often ‘open-ended’, much of the experimental work is
structured so that the pupils do obtain an answer to a real problem. It is hoped
they will thus experience the excitement of a discovery which is a genuine one for
them.
Efforts have been made throughout to place responsibility on the pupils, for
example by caring for living things, or handling expensive equipment, and by
careful observation and recording. Much, though by no means all, of the experimental
work is organized as a ‘circus’. In a ‘circus’ a great variety of pupil investigations
are related to a central concept. The pupils gain a common core of
experience by working at their own pace on the investigations, which can be
taken in any order. It is not essential for every pupil to do every investigation.
The pupils use worksheets containing questions based on each stage of investigation,
and the completed worksheet becomes part of the pupil’s own record.
Although much of the work is based on pupils’ investigation, there are areas, for
example radioactivity, where demonstration is essential.
B.7.3
Content of the course
The wide range of ability and interest in the pupils concerned indicated the need
for flexibility and adaptability in the material to be produced. The Nuffield
Secondary Science material is therefore not a course but material from which
teachers should be able to construct courses suitable for their own pupils. The
material is based on eight themes regarded as fundamental for all the pupils. The
themes and their constituent fields of study are as follows:
Theme 1 The interdependence of living things
1.1 Environmental studies, classification and identification
1.2 Basic exchanges
1.3 Animal and plant growth. Population studies
1.4 Disease, pest and weed control. Colonization
Theme 2 Continuity of life
2.1 Animal and plant reproduction and propagation
2.2 The mechanism of inheritance
2.3 The process of evolution
Theme 3 Biology of man
3.1 Physical activity
3.2 The human life cycle: Reproduction, growth and development
3.3 Health and hygiene
3.4 Senses, behaviour and learning
3.5 Man in the world -control of the environment
Theme 4 Harnessing energy
4.1 Energy in action
4.2 Man’s energy; his physical limitations and the use of machines
4.3 Electrical transmission of energy
4.4 Problems of bringing energy to bear
352 Details of Various Projects

Theme 5 Extension of sense perception
5.1 Human limitations -extending the range of sense perception
5.2 Hearing and the nature of sound
5.3 Seeing and the nature of light
5.4 Artificialaids to communication and recording
Theme 6 Movement
6.1 Transport
6.2 Natural movements of living things
Theme 7 Using materials
7.1 Introduction : collection. classification and preliminary investigations
7.2 Metals and alloys
7.3 Fuels
7.4A Building materials and modern plastics
7.4B Cleaning and coating materials
7.4C Fibres and fabrics
7.5 Radioactive materials
Theme 8 The Earth and its place in the universe
8.1 Getting away from the Earth
8.2 The Earth and its neighbours in space
8.3 The weather
8.4 The Earth’s crust
B.7.4
<strong>Teaching</strong> the course
The intention is that teachers wil select their ‘routes’ so that the pupils wil work
on material from all eight themes, more emphasis being given to the areas which
have greater significance for the pupils concerned. Some themes will thus have a
major treatment and others a minor treatment. Within each theme, each field of
study would be given a major or minor treatment or possibly even omitted.
Although certain themes may appear to lean towards one or other of the traditional
sciences, the content is by no means confined to one discipline. The
boundaries between the sciences are blurred and often disappear and attempts to
break the material into separate disciplines would often destroy the significance
of its content. The overlapping between themes and the many linkages that exist
between them enable teachers to construct a balanced and coherent course.
There are many areas in a number of the themes where there is an overlap with
other areas of the curriculum. It is very much hoped that in these areas close
cooperation between the science teachers and their colleagues in other disciplines
wil develop.
Much of the work can be used in any of the three years of the course depending
on the ‘route’ through the material which the teacher chooses. Certain concepts
do, however, need to be established early in the course if other work is to be
developed satisfactorily. Some work is more suitable for the younger pupils while
other areas require the more mature approach of the 16-year-old pupil.
353 Nuffield Secondary Science Project

The project was under the direction of Mrs Hilda Misselbrook, Nuffield Foundation
Science <strong>Teaching</strong> Project, Chelsea College of Science and Technology, London, S W 6, UK.
The material, published by Longman, Harlow, Essex, UK, consists of ten volumes, one
for each theme, a Teacher’s Guide and an Apparatus Guide. Background readers for the
pupils are planned on a number of topics but there will be no pupil’s text <strong>books</strong> as such. A
number of film-loops and sets of transparencies have been designed as an integral part of
the material.
Some laboratory equipment has been especially designed for the work though much of
the apparatus needed should be available in any well-equipped laboratory. With considerable
emphasis on investigation by pupils and a great variety of experimental work,
laboratories need to be capable of adaptation to many different types of uses and to have
considerable storage space.
B.8 Nuffield Advanced Physics Project
The Nuffield Advanced Physics Project is one of four advanced projects sponsored
by the Nuffield Foundation, all being two-year courses aimed at the 16-18
year age group, mainly those in the sixth forms of British secondary <strong>school</strong>s. The
other advanced projects are in Biological Science, Chemistry and Physical
Science. The four advanced projects are consistent in aims with the previous
Ordinary level projects and follow on from them in content.
The students for whom the work of the project is intended are a rather highly
selected group. Most will have performed well in a public examination at age 16
(General Certificate of Education, Ordinary Level), and wil take another public
examination after two years (General Certificate of Education, Advanced
Level). About half those taking <strong>physics</strong> at this level wil go on to some form of
further education involving <strong>physics</strong>, this being nearly three-quarters of those
who pass the Advanced Level examination. (The difference arises from those
important and too often disregarded students who fail the examination.)
But ‘further education involving <strong>physics</strong> ’ covers a wide variety of courses,
experiences and demands upon students. Proportions, each of the order of ten
per cent or less of the students in the class, wil go on to university courses in
Physics, Chemistry, Chemical, Mechanical or Electrical Engineering (and combined
engineering courses), Mathematics, Biology, Medicine, Dentistry; or
into a variety of college courses including training for science teaching (a desperately
small proportion).
Whilst at <strong>school</strong> these students show a corresponding variety of interest and
ability, and this variety is on the increase. The two years in the sixth form are
partly a preparation for further education (in some countries outside the United
Kingdom, corresponding work is carried on in colleges and universities) and
partly a completion of general secondary education. The aims of the project
had to respect both these aspects.
354 Details of Various Projects

B.8.1
Objectives
Learning in the future. The obvious need for students’ learning to prepare them
for later studies is at once confronted by the wide variety of those studies. This
difficulty is not diminished by any reflection about the needs of students in their
careers after further education, for there, too, there is much variety and, more
important, constant change. These people wil have to learn new jobs, some of
which do not yet exist, and make decisions about problems we cannot now
foresee.
An early decision was taken not to worry too much about lists of ‘things
people ought to know about ’. In face of the wide and shifting variety of future
needs, such lists are always long and usually fragmentary. The project has, instead,
held the view that the practical solution is to try to help students to become
better able to learn later in life what they then need to know.
Much future learning wil be from <strong>books</strong>, so parts of the work proposed are
designed to encourage selective and critical reading. Students are encouraged to
take the initiative in the learning process, for example, by arranging that from
a group of experiments a student does one of them and reports to the rest of the
class, who have to learn from him or her. Notes or summaries are sometimes prepared
by one student for the others.
In common with most other science teaching projects the content of the proposed
course is largely restricted to fundamental and generally useful concepts,
such as those of energy, momentum, charge, field, potential, oscillation, waves
and randomness, which seem likely to have lasting value in many branches of
physical science and engineering.
There is also an attempt to develop mathematical skills within the teaching of
the <strong>physics</strong> in the course. Again, the effort is selective. Ideas about rates of change,
first and second order derivatives and simple differential equations are given considerable
emphasis, whilst at other times mathematics is evaded if necessary.
Numerical methods are frequently used, in ways which may later help those who
use computers in problem solving.
Understanding <strong>physics</strong>. The course aims to make students better able to take
constructive, relevant steps towards the solution of problems for which they have
not been given complete, explicit rules of solution. This aim (phrased with some
care) is meant to be a realistic one. It seems clear that most of the demands of the
future on a student wil be new and problematical, while few wil require him or
her merely to recall items earlier learned. But few people can quickly or completely
solve a new problem, and the project organizers have taken the mark of
the educated physicist to be the ability to tell the relevant approach from the
irrelevant one, the more promising line of attack from the less, the helpful combination
of ideas from the unhelpful.
Understanding how <strong>physics</strong> works. The course aims to make students better able
to discuss and reflect cogently upon the process of inquiry in <strong>physics</strong>. This aim
is in part an aspect of the general scientific education with which education in
355 Nuffield Advanced Physics Project

<strong>school</strong>s is concerned, but may also prove to contribute to later learning, where
distinctions between, say, hypothesis, theory and test may be implicitly required
in reading without being made very explicit. We have also had it in mind that
students of the same age studying the humanities are concerned with large
matters of morality and principle, and that the self regard of science students
may be advanced by the inclusion of some of these broader issues.
It is just possible that some future decisions by men of affairs wil more adequately
reflect the potentialities and limitations of scientific methods if such
material is included in science courses.
Learning to inquire. Much <strong>physics</strong> teaching is, perforce, about <strong>physics</strong> rather
than of <strong>physics</strong>. The course seeks in some measure to increase the student’s
ability and willingness to inquire for himself. In particular, it includes two individual
investigations on a small, personal, freely chosen topic. Each occupies
around ten hours of class time (roughly the time allocated to <strong>physics</strong> within two
weeks). They are correspondingly modest in scope: for example, ‘how a rubber
band stretches’, ‘how water drips from a jet’ or ‘how a battery runs down’.
Awareness of practical and social implications. It is hoped that students wil become
more aware of the practical applications and social implications of the
<strong>physics</strong> they learn. Parts of the course are given a deliberate applied flavour, emphasizing
the ways in which engineers put things together for a purpose, in contrast
to the ways in which physicists take things apart in order to understand
them. This is clearest in the section on electronics, which is wholly devoted to
uses of combinations of circuit blocks and hardly at all to how the blocks work.
Such an approach to electronics reflects the further belief that this is nearest to
the real needs of people who use electronics, as do increasing numbers of
scientists.
The course also creates opportunities for discussion of the social consequences
of developing knowledge, particularly through a series of background
articles included within <strong>books</strong> for students.
Interest and enjoyment. The course aims to increase the interest in and enjoyment
of <strong>physics</strong> by as many students as possible (not just the able and highly motivated
minority). It does so not only because there is a need for future scientists
who are unlikely to appear unless students enjoy their work and want more of it,
but, in the last analysis, because those working on the project value the subject
and hope that others wil do so too.
B .8.2
Evaluation
Twenty-four <strong>school</strong>s, with nearly five hundred students, began a first version of
the two-year course after one year of preparatory planning and writing. A year
later, thirty-five additional <strong>school</strong>s (including two colleges of further education)
with eight hundred students began a revised version of the course, as did new
356 Details of Various Projects

students in the original <strong>school</strong>s. The final version wil reflect experience gained
with both groups of <strong>school</strong>s over a three-year period. The evaluation activities
undertaken with these <strong>school</strong>s are outlined below.
Feedback from teachers. Teachers were asked, for each part of the course, to
complete forms dealing with the adequacy of experimental instructions, the
clarity, usefulness and difficulty of questions written for students, the effectiveness
of sections of proposed teaching and the value and impact of background
reading. They were also invited to write at length on spare copies of the teachers’
guides, giving further criticism or suggestions, many of which have been very
helpful.
Written comments froin students. Students have been invited to write to the project
about their feelings concerning each section of teaching. The response has
been very considerable. It has afforded insight into some difficulties not easily
obtained in other ways, and has made it possible to modify material for students
which was being produced for later sections in the light of reactions to earlier
sections. The conflicts of opinion revealed have served as a useful check on any
over-simple view as to the interest, value or effectiveness of individual parts of
the course. Among other things, these responses have shown that a proportion
of students think they are chiefly interested in material which relates the <strong>physics</strong>
they learn to its practical uses. An attempt is under way to extract reasonably
objective information from these unstructured student responses. If this proves
possible, it may provide a new and valid way of obtaining information not
subject to the constraints of structured questionnaires.
Visits to <strong>school</strong>s. An essential element in the work of the project has consisted of
visits to <strong>school</strong>s by members of the team or their representatives. Although they
have been mainly concerned with establishing and maintaining personal contact
and confidence, these visits have also afforded many valuable insights into the
difficulties of translating the project’s proposals into practice.
Class tests. Short tests were sent to <strong>school</strong>s at the completion of most sections of
teaching, together with one or two tests covering longer periods of time. While
these tests have primarily served to indicate progress to students, their results
are being correlated with those of other tests. Students beginning the course
complete standardized tests of reasoning and of spatial ability. Suitable standardized
tests of attitudes were not available, so in the first instance a questionnaire
on interests and career intentions was sent out. This has been developed
further into a questionnaire in which students place their feelings about aspects
of <strong>physics</strong> and about the learning of <strong>physics</strong> on a scale between a series of pairs
of polar adjectives (semantic differential). At the same time information about
their previous history was collected. Where appropriate, tests are given when
students have completed the course in order to obtain information about
changes that may have taken place.
357 Nuffield Advanced Physics Project

Public examinations. The two-year sixth form course in British <strong>school</strong>s is organized
around the General Certificate of Education Advanced Level Examination,
administered by several public Examination Boards. The project has, with the
cooperation of the Boards, developed its own Advanced Level examination,
which is intended to reflect and reinforce the aims of the project so far as is
possible.
B.8.3
The content of the course
The block diagram indicates the content of the course. The content is organized
around three broad themes (shown as columns in the diagram), which represent
three important and different styles of thought or kinds of concern within
<strong>physics</strong>. One concerns the moves continually made by physicists from the
macroscopic to the microscopic, seeking understanding of matter in terms of
atoms and of atoms in terms of more fundamental building bricks. Another
theme centres round the field concept, the problems of action at a distance and
the many uses of field and potential ideas within <strong>physics</strong>. The last is more
analytical, being about problems of change and motion, of predicting what will
happen next given what is happening now. It embraces dynamics, oscillations,
waves and some of the statistical ideas behind thermodynamics.
The existence of these themes is meant to become explicit as the course proceeds
in pursuit of the third aim mentioned above, understanding how <strong>physics</strong>
works. But the course itself moves freely from theme to theme, using an idea
just learned in one context again in a fresh one, partly to assist the aims of
learning in the future and of understanding <strong>physics</strong>, and partly to show this
cross-connection of ideas as a feature of the subject itself.
The course is also organized towards a final, focal end-point; a study of the
wave-particle behaviour of electrons and photons, and of the nature of simple
atoms. There are many reasons for building the course in this way. It makes it
into a connected and coherent story, in which each part has a purpose. At the
end much earlier work is reviewed in a natural and helpful way. Ideas developed
in one context are shown at work in another, so that students may come to
expect such fruitfulness on other occasions. The whole can illustrate the complex
patterns in which new theories develop out of old ones, in which theoretical
ideas at one stage are treated like facts for another stage or in which experiments
suggest new ideas and ideas suggest new experiments. The particular
end-point chosen has the further advantage of being a genuine revolution in
science: the most important event in <strong>physics</strong> in this century and one with
implications for many other sciences.
The course is arranged in a series of ten units, so as to encourage flexible use
of the materials in the future. The following brief and selective notes mention
some features of each unit which may be of general interest.
358 Details of Various Projects

Electricity. field conceprs Nafure of mafrer and atoms Motion and change
t
Conduction; charge carriers:
Electrons; electron-atom
current and potential
collisions: energy level
Dynamics; energy and
differences: electrical energy: * evidence from inelastic
momentum
charge
collisions
?I
L 1
Decay of charge on
r.
caDacitor
Electric field; parallel plate
capacitor; gravitational field
Ionic bonding in sodium
and potential, electric inverse
chloride
square field and potential.
Waves; radio, light,
microwaves, sound,
L r
velocity of a mechanical
wave
uiit
J-
J
4
Oscillations, simple
harmonic motion,
Radioactivity: Rutherford
t
atom; periodic properties of tf randomness, exponential
function
"7
4
induction. motors, transformers
Unit 6
J.
r .
A
Unit 7
I
Physical optics,
polarization
t
I
Electromagnetic waves -.
Relativity
J
7'
t
Unit 2
I
Waves, particles, atoms; dual
behaviour of photons and
electrons: atoms as standing
,wave systems; uses of wave
Statistical ideas behind
thermodynamics; heat
flow; world fuel re<strong>source</strong>s
7,
t
Unit 10

Unit 1 Materials and structures. This is planned as an introductory unit. It is
deliberately applied in flavour but also raises for the first time issues that wil be
important in the course, such as the significance of models. Student reading is
suggested for the study of modern composite materials, again an early start on
a teaching method used later.
Unit 2 Electricity, electrons and energy levels. This unit is long but varied. It
reviews previous work and uses simple individual experiments for students to
clarify ideas of current, charge and potential difference. Dynamical ideas are reviewed
where they are needed. Evidence for energy levels from electron-atom
collisions comes partly from laboratory experiments and partly from reading of
selected extracts from papers. The decay of charge on a capacitor is used to
develop ideas of rates of change and the differential equation is integrated
numerically.
Unit 3 Field andpotential. Electric and gravitational field and potential are compared
to bring out the generality of the field concept and the value of the formal
analogies between them. The ideas are used in a study of ionic bonding, here
using semi-programmed material.
Unit 4 Waves and oscillations. The superposition property of many waves is
shown experimentally, and some evidence emerges for the unity of the electromagnetic
spectrum. Students can measure the velocity of light and of microwaves.
The calculation of the velocity of one type of mechanical wave serves to
illustrate that wave velocities can be calculated from basic laws.
Mechanical oscillations are used to extend ideas about derivatives, and the
differential equation is integrated numerically. Empirical experience of standing
waves prepares for unit 10.
Unit 5 Atomic structure. This unit again involves much reading by students from
texts and selected papers. It also introduces the exponential function by way of
an analysis of radioactive decay, and there is a first discussion of the problems of
randomness.
Unit 6 Magnetic Field. This unit is as practical as possible, dealing with electromagnetic
machines of several kinds, but includes the theory needed for the
description of electromagnetic waves in unit 8.
Unit 7 Reactive circuits and electronics. Reactive circuits and some simple
electronic circuit elements (all based on one basic unit) are put together as
building bricks to serve a variety of useful functions. In this system’s approach
the emphasis is on use and on putting things together, rather than on analysis
and detailed explanation.
360 Details of Various Projects

Unit 8 Electromagnetic waves. This unit draws together some threads from
earlier work, relating experiments in wave optics and polarization to a discussion
of the nature of electromagnetic waves. This leads to a brief mention of some
relativistic problems.
Unit 9 Change and chance. This unit tries to bring out, in a discussion of statistical
ideas underlying thermodynamics, the importance for <strong>physics</strong> of the idea
of randomness. Film shown backwards suggests the notion of irreversible
events, and diffusion is taken as a simple example. The irreversible use of the
world’s fuel re<strong>source</strong>s shows that the idea has important implications. Then a
counter-and-dice model of a simple (Einstein) solid is used to show how heat
flow from hot to cold may be seen as an irreversible statistical process. Film
generated by computer is used to supplement student experiments, so that the
influence of large numbers of quanta and atoms can be seen. The Boltzmann
factor and the entropy concept can emerge.
Unit 10 Wazies, particles and atoms. Units 8 and 9 represent minor end-points
of the course; in this major end-point many more ideas come together in new
patterns. Ideas of waves, energy; and momentum are related to wave-particle
duality. The electric potential well in a nuclear atom is seen as a ‘box’ containing
electron standing waves, and is used to explain the existence of energy
levels. Some students wil be able to use the numerical methods developed earlier
to solve a one-dimensional Schrodinger equation for a hydrogen atom. The
importance of wave-mechanical ideas for <strong>physics</strong> and for other sciences is outlined.
It is hoped and expected that <strong>school</strong>s which take up the materials wil adapt
their sequence and content as time goes by. The course is organized into units
to make such flexible use relatively easy. It is also to be hoped that some units
wil be of use in college and university courses, and in curriculum development
in other countries.
The project is under the direction of Dr P. J. Black of the Physics Department, The University
of Birmingham, UK and J. M. Ogborn. Chelsea College of Science and Technology,
London, S W 6, U K.
Units 1 to 8 are published in the form of a detailed teacher’s guide and a student’s book.
The student’s <strong>books</strong> are not texts, but include material not found in otherwise-suitable
texts. in particular, many questions including some semi-programmed material, background
reading and summaries. Units 9 and 10 contain treatments of topics that are too
new to this level of education to be found in present texts, and so for these the teacher’s
guide and student’s book is combined in one volume containing text, questions and
suggested experiments. The <strong>books</strong> are published by Penguin Books Ltd, Harmondsworth,
Middlesex, U K .
361 Nuffield Advanced Physics Project

B.9 NufEeld Advanced Level Physical Science Project
This is one of the four advanced projects sponsored by the Nuffield Foundation
for boys and girls, normally between the ages of 16 and 18, of above average
ability, during their last two years at <strong>school</strong>, before going on to higher education.
(It is customary for boys and girls in English <strong>school</strong>s who aim at higher education
to follow Advanced courses in three subjects related to their future studies.)
The other three Nuffield advanced courses are Physics, Chemistry and Biology
as separate subjects. The Physical Science course provides an integrated course
which, for those pupils who study it, replaces the last two years of <strong>physics</strong> and
chemistry at <strong>school</strong>.
The underlying reasons for developing the physical science course are twofold.
In the first place it is believed that the student gains a great deal from an integrated
approach to physical science at this level. In the second place physical
science requires the time allocation of only one A-level course. Nevertheless all
university departments which require an A-level background in <strong>physics</strong> or
chemistry or both subjects are accepting the physical science course as providing
a sufficient background. This means that students can follow a wider overall
course than otherwise during their last two years at <strong>school</strong>. For instance, many
who would have studied mathematics, <strong>physics</strong> and chemistry have instead
studied mathematics, physical science and an arts subject such as economics.
Many who would have studied <strong>physics</strong>, chemistry and biology have instead
studied mathematics, physical science and biology, and so on.
B.9.1
Description of the course
Special features are: (a) Division into a basic course (about 75 per cent of the
total time) and options (about 15 per cent); (b) Allocation of time for a student
project (about 10 per cent of course time); (c) An emphasis on materials, both
in the basic course and in the options.
The general scope and level of treatment can perhaps be judged from the
following summary. It should be emphasized that this summary is not a teaching
order. Some topics must inevitably be taken in a certain order but, in general,
the individual teacher is encouraged to develop his own teaching order.
Experimental work, both demonstrations and work by individuals or small
groups, is an essential part of the course, and is at all times completely integrated
with the overall development.
The basic course:
1 Forces, motion and energy. Newton’s laws; normal acceleration and central
forces; linear momentum and its conservation; kinetic and potential energy;
conservative force fields.
2 The elements of the second short period, Physical and chemical properties of
the elements, their oxides and their chlorides ; amount of substance; determination
of formulae.
362 Details of Various Projects

3 Kinetic theory and phase equilibria. Evidence for the particulate nature of
matter; the limiting behaviour of real gases; pY = nRT; the distribution of
molecular speeds and energies; molecular collisions and mean free path;
vapour pressures and phase diagrams ; the vapour pressure criterion for equilibrium
between condensed phases.
4 Some important chemical reactions. The significance of a chemical equation;
the determination of stoichiometry; heat of reaction and thermochemical calculations;
acid-base reactions as proton-transfer processes; complex formation;
oxidation numbers; redox reactions as electron-transfer processes.
5 Electric and magnetic fields: atomic structure. Coulomb’s law; field intensity
and potential ; constant electric fields and Millikan’s work; capacitors ; the force
on moving charges in magnetic fields; the determination of e/m; the mass
spectrometer; e.m.f., potential difference and Ohm’s law; a-particle scattering
experiments and the ‘nuclear’ atom; ionization energies and the arrangement of
electrons in atoms.
6 Chemical equilibrium. Electrode potentials; the approach to equilibrium in
redox systems ; the equilibrium law; equilibria involving complex ions ; acid-base
equilibria and pH; buffer solutions and indicators; the meaning and significance
of AG for a chemical change; enthalpy and entropy factors in chemical reactions;
the connection between AG and K.
7 Intermolecular and interatomic forces; structure andproperties. The structures
of simple solids and liquids; the nature, range of action and magnitude of intermolecular
forces; potential energy curves and physical properties; the structures
and energetics of ionic crystals; the hydrogen bond; types of bond and units of
structure in solids.
8 An introduction to chemical kinetics. The experimental determination of reaction
orders and rate constants ; rate equations and reaction mechanisms; the
effect of temperature on reaction rate; activation energies and their interpretation.
9 The elements of a periodic group. Group similarities, as exemplified by the
elements of group I and their compounds; physical and chemical properties of
the elements of group IV and of their more important compounds; general
trends in the properties of the elements of a group, as illustrated by the elements
of group IV.
10 Some d-block elements. Evidence for electronic configurations from ionization
energies; oxidation states and their relative stabilities; chemical behaviour
of the elements in representative oxidation stages; formation of complex ions;
colour and catalytic activity; a more detailed study of a selected element.
363 Nuffield Advanced Level Physical Science Project

11 The chemistry of the covalent bond. Simple approaches to covalent bonding
and to molecular geometry; average bond energies; molecular polarity; some
general features of the chemistry of carbon; isomerism; alkanes and their reactions
; homolytic bond fission ; halogenated alkanes and nucleophilic reagents ;
substitution and elimination reactions; alkenes and electrophilic addition to
double bonds; benzene and the aromatic sextet; aromatic substitution reactions,
their importance and their mechanism; the more important reactions
of alcohols, phenols and amines; carboxylic acids and esters.
12 Simple harmonic motion and wave motion. Kinematic and dynamic approaches
to SHM; characteristics and examples of SHM; forced oscillations and resonance
; coupled oscillations ; progressive waves and their properties ; standing
waves.
13 Electromagnetic induction and electrical oscillations. Steady-field induction;
the ax. dynamo; characteristics of alternating current; peak and r.m.s. values,
phase and frequency; variable-field induction; self-induction; the behaviour of
resistors, capacitors and inductors with a.c. ; the parallel resonance circuit;
generation and characteristics of electromagnetic waves by oscillatory circuits.
14 Electromagnetic radiation. Interference and diffraction phenomena; the Bragg
relationship for X-rays and crystals; polarization properties and optical activity;
the photoelectric effect; the spectrum pf atomic hydrogen as evidence for energylevels;
the Rydberg constant and its uses; X-ray spectra; the Compton effect and
the de Broglie relationship; applications of the wave nature of matter.
The general options:
(Each student is advised to choose two general options.)
G1 An introduction to thermodynamics. Entropy, heat and the second law; spontaneous
changes and the second law; the evaluation of entropy changes; entropy
and probability; the variation with temperature of AG and In K; heat
engines ; fuel cells ; the thermodynamic temperature scale.
G2 Rate processes. Exponential growth and decay; the integration of chemical
rate equations and the accurate determination of rate constants; radioactive
growth and decay; growth and decay of the current in circuits possessing resistance
and capacitance or resistance and inductance.
G3 Rotational motion. An experimental approach to rotational motion; the
basic relationships and some of their applications; a.c. motors; the rotation of
molecules and microwave spectra.
364 Details of Various Projects

G4 The conduction of electricity. Some general principles; conduction by ionic
solutions; a simple approach to conduction by semiconductors ; conduction by
metals, a semi-classical approach.
G5 Methods of purijcation and criteria of purity. The equilibrium between a
pure solid and a solution; a general approach to separation and purification
processes; criteria of purity; a more detailed, largely experimental, study of
either distillation or chromatography.
G6 Molecular spectra and photochen2istrv. Molecular vibration frequencies ;
general features of near infrared spectra; electronic spectra of diatomic molecules;
general features of electronic spectra of polyatomic molecules; colour;
loss of energy by excited molecules ; principles of photochemistry.
G7 Further organic chemistry. Aldehydes and ketones; nucleophilic attack on
the carbonyl group; carboxylic acids and their derivatives; some synthetic
methods: optical isomerism; amino-acids; polypeptides and proteins.
The materials options:
(Each student is required to choose one materials option.)
M1 Metals. Atomic arrangement in metals and alloys; examination of metal
surfaces ; crystallization and grain structure of metals and alloys ; elastic behaviour;
plastic deformation; increasing the strength of metals and alloys;
mechanical failure of metals and alloys.
M2 Polymers. General characteristics; condensation polymerization ; vinyl polymerization;
chain structure of vinyl polymers; stereospecific polymerization ;
manufacture and fabrication ; polymers in solution, molecular weights ; crystallinity
and the effect of temperature; rubbers; fibres; mechanical properties;
miscellaneous properties.
M3 Ceramics and glasses. Crystalline and glassy forms of silica; nature of the
vitreous state; types of glassy ceramics; crystalline ceramics : crystal-glass
ceramics; mechanical properties; electrical, optical and thermal properties ;
preparation of glasses; fabrication and toughening of glass articles ; technology
of clay-based ceramics; technology of crystalline ceramics.
The project
Students carry out a practical project on any topic relevant to the physical
science course. It may comprise the design and construction of a piece of apparatus
or of some mechanical device; it may take the form of a small research-type
investigation; or it may simply involve a more complete practical study of some
aspect of physical science than is possible as part of the general practical work
365 Nuffield Advanced Level Physical Science Project

of the course. A small report is written on the work carried out and the results
obtained.
Each project is assessed by the student’s own teacher, according to a scheme
provided by the physical science examiners. This gives weight to such factors as:
originality and initiative; general organization of the work; accuracy; writing
of the report; amount of help given, and so on. The examiners visit each <strong>school</strong>
at intervals so as to form a picture of the general level of the work, and in this
and other ways they coordinate the teachers’ assessments and scale their marks
up or down as the case may be.
The Nuffield A-level Physical Science Project is directed by Dr J. E. Spice, Winchester
College, Hampshire, UK. The following <strong>books</strong> are published by Penguin Books Ltd,
Harmondsworth, Middlesex, U K:
(1) Introduction and Guide, (2) Teachers’ Guide: Basic Course, (3) Teachers’ Guide:
Options, (4) Students’ Workbook: Basic Course, (5) Students’ Workbook: Options,
(6) Collection of Multiple Choice Questions, (7) Source Book for Students, (8) Data Book
(jointly with Nuffield Advanced Level Chemistry and Physics courses).
B. 10 Physical Science for Nonscience Students: The PSNS Project
The purpose of this project was to produce material for a one-year laboratoryorientated,
college level physical science course for students not specializing in
science.
The overall objective is to convey to non-science students an appreciation of
the power of the scientific method by providing them with opportunities to
observe physical phenomena, to generate models consistent with their observations,
to reason from their models to the results of controlled experiments, and
to perform experiments and analyse experimental data. If these experiences are
provided at a pace and level appropriate to students who have reached college
without previously having enjoyed success in learning science or mathematics,
then these more specific objectives may be realized :
(1) to help non-science students realize that the systematic study of science can
be enjoyable;
(2) to provide students with the elementary concepts and experimental techniques
needed to study science independently ;
(3) to improve the attitude of non-science students toward the goals and methods
of scientific study;
(4) to generate in prospective teachers confidence in their own ability to pose
meaningful scientific questions and to seek answers through experimentation and
logical thought.
The PSNS course is designed to serve college students who have not previously
enjoyed a meaningful science experience. It is suitable for college freshmen,
but would also serve older or slightly younger students. No special background
in science or mathematics is necessary for P S NS students. Sufficient intellectual
366 Details of Various Projects

maturity to enable students to recognize valid logical reasoning is essentQl.
Students who have succeeded with laboratory science courses, or who possess
sophisticated mathematical skills, may wish to take a more quantitative course.
B. 10.1 Description of the course
The PSNS course is a laboratory-oriented programme which focuses on a
single theme, the structure of solids. Only topics which aid students in mastering
concepts related to the structure of solids are included in the main text. This
includes a variety of topics from the fields of <strong>physics</strong> and chemistry. The experimental
work is an integral part of the course and is woven inextricably into the
fabric of the text.
The major topics covered include : wave motion, interference, and diffraction;
the relationship between motion and the forces which cause it; energy in various
forms and the conservation of energy during interactions between systems; the
effects of heat on matter and the kinetic theory of matter; electrical forces and
their importance in binding particles of matter together; models for the structure
of atoms, molecules, and crystalline solids ; the relationship between structure at
the atomic level and the properties of matter. These concepts are introduced
through experimental work. Either experimental results lead students directly to
generalizations about relationships between measurable parameters, or concepts
are introduced in the process of developing particle models which are
consistent with a set of observations. In either case it is direct experience with
physical phenomena which stimulates interest in the topics under study and which
motivates efforts to create a theory to relate a set of observed facts.
The emphasis in the course is on the processes of observation, model-making
and logical reasoning. Students are expected to participate in pre-laboratory discussions
during which they attempt to isolate questions of interest and plan experimental
means for seeking answers. Equally important are post-laboratory
discussions during which experimental results are organized and analysed. It is
at such times that students are asked to propose models consistent with their
observations. Other data, including the results of additional experiments when
appropriate, are introduced to support or suggest modifications of the models.
In addition, questions and problems are provided in the text which help students
to develop these analytical skills and also suggest fruitful lines of thought.
Very little in the way of mathematical analysis is required of the students. The
course is quantitative in the sense that students collect numerical data and attempt
to determine its consistency with mathematical relationships. However, long
chains of deductive logic using abstract symbols are rarely exhibited. Among the
exceptions are some algebraic analyses of wave interference and diffraction
patterns, which are included because of the crucial role X-ray diffraction plays
in determining the structure of crystals.
In addition to the goals described above, it is hoped that students wil gain
some understanding of the behaviour of matter and how its properties can be
understood in terms of particle models. Though this subject is not the only one
367 Physical Science for Nonscience Students: The P S N S Project

which could be used to illustrate the processes of scientific investigation and
analysis, it provides a good vehicle for introducing concepts and techniques employed
by both chemists and physicists. By making no attempt at encyclopedic
coverage of all fields of physical science, these materials have some chance to
exhibit forcefully major styles of scientific thought and procedure.
The supplementary volume contains chapters entitled :(1) Matter in the Earth;
(2) Matter in the Astronomical Realm; (3) Equilibrium; (4) Magnetism; (5)
Geometrical Optics. One or more of these can be inserted among the chapters of
the main text to add diversity to the programme when the length of the course,
the ability of the students and the interests of the instructor warrant.
The Teachers’ Re<strong>source</strong> Book provides assistance to the instructor in four ways :
(1) it suggests a rationale for the selection and style of treatment of topics; (2) it
provides essential advice on the use of experimental apparatus and hints on how
to guarantee successful experimental results ; (3) it supplies detailed answers to
all questions in the text; (4) it provides suggestions on ancillary teaching aids
such as references and films.
The table of contents for the main text is as follows:
Chapter 1 You and physical science
Chapter 2 When, where, and how much?
Chapter 3 A look at light
Chapter 4 Interference of light
Chapter 5 Crystals in and out of the laboratory
Chapter 6 What happened in 1912
Chapter 7 Matter: a closer look at differences
Chapter 8 Matter in motion
Chapter 9 Energy
Chapter 10 The kinetic theory of gases
Chapter 11 Bonding forces within a crystal
Chapter 12 Electric charges in motion
Chapter 13 Models of atoms
Chapter 14 Ions
Chapter 15 The nature of an ionic crystal
Chapter 16 Molecules
Chapter 17 Non-ionic materials
Chapter 18 What it is all about
The project was under the direction of Professor Lewis Bassett and Professor Walter
Eppenstein, Rensselaer Polytechnic Institute, Troy, New York. Further information about
the project can be obtained from the Associate Director and Chairman of the Advisory
Board, Professor A. A. Strassenburg, Department of Physics, State University of New
York, Stony Brook, New York 11790, USA.
The need for this project was identified by the Commission on College Physics and the
Advisory Council on College Chemistry. A grant for the project was awarded by the
National Science Foundation to Rensselaer Polytechnic Institute in the spring of 1965.
The number of the teachers who have adopted the entire course is 150 and the number
of students involved is 16000.
368 Details of Various Projects

The following materials can be ordered from John Wiley & Sons, 605 Third Avenue, New
York, NY 10016, USA:
(1) The main text: An Approach to Physical Science, (2) A volume of supplementary
chapters, (3) A Teacher’s Re<strong>source</strong> Book (The original version covered only the chapters
in the main text. A revised version includes material matched to the supplementary
chapters also.),(4)A complete inventory of the apparatus needed to perform the experiments
described in the text.
B. 11 The Portland Integrated Science Project
The purpose of the project was to improve the science curriculum in secondary
<strong>school</strong>s. It grew out of earlier work by the Portland Project Committee when an
integration of <strong>physics</strong> and chemistry was achieved. The course which it produced
is a three-year sequence, Although it uses substantial portions of Chem
Study and Harvard Project Physics, approximately one-half of the content of
the course, including the biology and biochemistry sections, was prepared by the
Portland Project Committee.
The material is intended for use in the last three years of American high <strong>school</strong>s,
for pupils age 15-18, of average or above average ability. It is equally suitable
for boys and girls. No previous formal experience of science is necessary for
pupils studying the course. A basic knowledge of arithmetic and algebra is
necessary. Some knowledge of trigonometry is desirable, but not essential. No
previous knowledge of calculus is necessary, nor is formal knowledge of statistics.
The intention is to equip pupils with some of the skills and modes of behaviour
which are characteristic of the working scientist, and at the same time to capture
their interest and enthusiasm for later encounters with science.
B. 1 1.1 Description of the course
Thefirst-year course. This consists of four parts: (1) Perception and Quantification,
(2)Heat, Energy and Order, (3) Mice and Men, (4)Environmental Balance.
The year begins with a study of the perceiver, moves on to the perceived, and
ends with the interaction of the perceiver with the perceived. The first-year student
starts out by gaining a better awareness of the nature of his perception and
senses, the faculties that make him aware of the world around him. With an increased
understanding of these perceptual abilities, he can turn to the environment
and then relate himself to it. He finds that his perception is limited and that
he often needs to call on technological and conceptual extensions and that even
these have their limitations.
The importance of organization and classification as parts of perception is
emphasized. The physical properties of matter are introduced and studied as
aids in organization and classification of chemicals. The culminating experiment
of the Perception unit is to organize the data on punched cards.
Apart from the great diversity exhibited in nature, which the scientist must
organize in order to comprehend, certain unifying principles are essential for
369 The Portland Integrated Science Project

deeper understanding. The most powerful of these is the energy concept which
is explored in the Heat, Energy and Order unit in several of its ramifications,
physical, chemical and biological. The discussion begins by developing an experientially
important energy form, namely heat. The macroscopic aspects of
heat as embodied in calorimetry are related to the microscopic in terms of random
molecular motion. This builds confidence in the idea of the atomic nature
of matter which is essential to much of the unit. Various energy conversions form
the vehicle for extending and generalizing the energy concept. Nuclear energy is
developed in sufficient detail to underscore its environmental and social significance.
Finally, the thermodynamic limitations and implications of energy
conversion are explored, ending with a view of life as a supremely artful organizer
in nature, a mechanism powered by energy which creates wondrous ‘local order’,
but always at the expense of influencing its environment.
The growth of a mouse colony carries the thread of the unit, Mice and Men.
As it develops, students learn many things about the concept of population. The
food and water consumed and the products eliminated tie the mouse colony back
to the unit Heat, Energy and Order and point ahead to the chapter on communities
and to the unit Environmental Balance.
The cell concept is given prime position in this unit and is used to enter topics
on reproduction, embryology and matdration which are observed in the mice
and other organisms. The mice selected for the original colony are such that an
experiment in Mendelian genetics comes out of the observations students make
as the colony develops. In most of the chapters man is an important organism
and receives as much attention as the mouse, although the data are often secondhand.
A fact that must be faced is that, as our population increases and human
activities are directed towards increasing the standard of living for this population,
strains are placed upon the environment. As students discovered in Mice
and Men, the size of the community has a relation to both the quantity of the
food, water and energy required and the quantity of waste products produced.
To develop the concept of a closed system and point out the necessity for environmental
management, an analogy between the Earth and a spaceship is made.
Students are then introduced by a multimedia approach to the nature of some of
our common pollutants (with emphasis upon air, water, heat, noise and radiation)
as well as their effects. Following this, students are encouraged to undertake
a rather detailed study of a particular type or aspect of pollutior. Emphasis
here is placed upon student activity, which may take any number of forms. The
culminating activity centres around discussion of these special studies together
with the complex relations involved within the environment. It is hoped that, out
of these studies, students wil become aware of the existing threats to man’s
future on this planet.
The second-year course. The second year of the course is considerably more
quantitative in its approach than the first. This is the case because (1) the students
are one year further in their mathematical preparation, (2)the students who elect
370 Details of Various Projects

to take a second year of science are more likely to exert the effort to master more
difficult topics, and (3) many of the quantitative aspects of <strong>physics</strong> and chemistry
are basic to an understanding of molecular biology, which is an important part
of the following year’s work.
The second year consists of two parts: (1) Motion and Energy, (2) Chemical
Reactions. The year begins with the study of motion, going from the quantitative
description of motion to a consideration of what causes motion and a discussion
of Newton’s laws. There follows the development of laws of conservation of
momentum and energy, including a discussion of energy in biological systems.
This section culminates with a discussion of kinetic molecular theory.
Due to recent advances in both molecular biology and biochemistry, the
descriptive approach to biology has gradually given way to one that is primarily
analytical. It is now necessary, even on the high <strong>school</strong> level, for the serious
biology student to have a more thorough understanding of those concepts normally
embodied in the ‘modern’ high <strong>school</strong> <strong>physics</strong> and chemistry courses. The
major objective of the unit Chemical Reactions is to build up some of those basic
chemical concepts that are necessary for an analytical study of both the unit, The
Chemistry of Living Matter and the unit Energy Capture and Growth.
The following sub-objectives of this section help in the realization of the major
objective: some of the topics discussed are the mole concept, equation writing,
energetics associated with chemical reactions, the dynamic nature of particles
and their interactions and the application of energy and equilibrium to chemical
systems.
The third-year course. This consists of four parts: (1) Waves and Particles, (2)
The Orbital Atom, (3) Chemistry of Living Matter, (4) Energy Capture and
Growth.
The underlying rationale of the third year is a study of energy and its importance
to life.The first thrust is to build the orbital model of the atom using, as
background, waves, electromagnetism and historical models of the atom. Once
the orbital model is established as a representation of the localization and the
directionalization of electronic energy, structural models are built to show how
biopolymers are spatially arranged and experiments are done to give evidence of
energy relationships. With shape, size and energy relationships of molecules
established. the DNA molecule is introduced. The culmination of this work
comes in the final section when photosynthesis is considered. With this topic
much that has gone before is brought to a logical focus.
These topics are most appropriately placed in the third year of the integrated
sequence after students have developed some facility with basic ideas from
chemistry and <strong>physics</strong> ; for example, quantitative knowledge about energy,
mechanism of chemical reaction, equilibrium, rate of reaction. the photon and
wave nature of light, electrical phenomena, and kinetic molecular theory. They
should not now simply parrot biochemical processes such as photosynthesis and
cell respiration but should understand the many chemical and physical principles
which underlie these processes.
371 The Portland Integrated Science Project

Time is alloted at the conclusion of the third year for individual investigation
and studies.
B.11.2 Outline of the course
First Year
Part One Perception and Quantification
I Sensing and perceiving
I1 Measurement, distribution, organization and communication
Part Two Heat, Energy and Order
I Heat
I1 Temperature and chaos
111 Energy
IV Nuclear energy and radioactivity
V Trends in nature
Part Three Mice and Men
I Reproduction and development
I1 Genetics
I11 Genetics and change
IV Populations
V Ecology
Part Four Environmental Balance
Second Year
Part One Motion and Energy
I Motion
I1 Newton explains
111 Multi-dimensional motion
IV Conservation
V Energy-work
VI Kinetic theory of gases
Part Two Chemical Reactions
I The mole as a counting unit
I1 Combinations of gases
111 A useful form of P-kDT
IV Chemical equations
V Electrical nature of matter
VI Basic particles
VI1 Energy effects in chemical reactions
VI11 Rate of reactions
IX Equilibrium
X Solubility
XI Acid-base
XI1 Oxidation-reduction
XI11 Stoichiometry
372 Details of Various Projects

Third Year
Part One Waves and Particles
I Waves
I1 Light
I11 Electricity and magnetic fields
IV Faraday and the electrical age
V Electromagnetic radiation
VI The chemical basis of atomic theory
VI1 The electrons and quanta
VI11 The Rutherford-Bohr model of the atom
IX Some ideas from modern physical theories
Part Two The Orbital Atom
I Atoms in three dimensions
I1 Many-electron atoms
I11 Ionization energy and the periodic table
IV Molecules in the gas phase
V The bonding in solids and liquids
Part Three The Chemistry of Living Matter
I Monomers and how they are built
I1 Polymers, or Stringing monomers together
111 Polymers in 3-D, or The shape of things to come
IV Where the action is-the active site
V How polymers make polymers
VI Genes, proteins and mutations
Part Four Energy Capture and Growth
I Energy capture
I1 Energy consumption and metabolism
I11 Metabolism and genes
The work began in August, 1966, at Portland, Oregon, USA, and was under the direction
of Dr Karl Dittmer and Dr Michael Fiasca, Portland State University, PO BOX 751,
Portland, Oregon 97207, US A.
The following materials are available :
First Year
1 Perception and Quantification: Student Guide and Teacher Guide
2 Heat, Energy and Order: Student Guide and Teacher Guide
3 Mice and Men: Environmental Balance: Student Guide and Teacher Guide
Second Year
4 Motion and Energy; Chemical Reactions: Student Guide and Teacher Guide
Third Year
5 Waves and Particles; The Orbital Atom: Student Guide and Teacher Guide
6 Chemistry of Living Matter; Energy Capture and Growth: Student Guide and Teacher
Guide
Little special apparatus is required other than equipment already commercially available
for Chem Study and Harvard Project Physics.
373 The Portland Integrated Science Project

B.12 PSSC Physics
The work of the Physical Science Study Committee (P S S C) is now so well known
since its publication in 1960, and it has already had such a profound influence
on so many other projects, that it is not necessary to include any account of it
in this volume.
B.12.1 PSSC Advanced Topics Program
. The Advanced Topics Supplement takes up additional fundamental ideas and
is meant as an extension of the P S S C course into a two-year course in American
high <strong>school</strong>s, or it can be used as part of an introductory course at college level.
The content includes (1) angular momentum, (2) statistical mechanics, (3)
special relativity, (4)quantum <strong>physics</strong>.
The Advanced Topics project was under the direction of Uri Haber-Schaim, Education
Development Centre, 55 Chapel Street, Newton, Mass. 02160, U SA.
The text, including the laboratory guide and the teachers’ guide, is obtainable from D. C.
Heath and Company, 285 Columbus Avenue, Boston, Mass. 021 16, USA; the apparatus
from Macalaster Scientific Corporation, 186 Third Avenue, Waltham, Mass. 02154, U S A
and from Scientific Electronics, 1085 Commonwealth Avenue, Boston, Mass. 02215, U SA;
the films from Modern Learning Aids, 1212 Avenue of the Americas, New York, NY
10035, USA. Achievement tests have been prepared for all chapters and are published by
Educational Testing Services, Princeton, New Jersey 08540, US A.
B.13 Course Development Project in Quantitative Physical Science: The QPS Project
The purpose of this project was to provide course material to enable the teacher
to teach successfully a course on physical science through guided experiences
rather than through a textbook.
The intention was to produce a stimulating course to serve as a general education
for the entire student body, and as a specific preparation for those who study
science and mathematics in grades ten to twelve, so that they wil derive more
benefit from those courses. It aims to have features which wil attract students to
science and mathematics instead of driving them away, and it can be taught with
reasonable success by teachers who majored in biology or mathematics instead
of physical science and in <strong>school</strong>s where faculty turnover is frequent.
It was primarily intended as a general education for the ninth-grader, average
age 14. However the first portion is being used successfully in the seventh and
eighth grades, and as a science course for eleventh- and twelfth-graders who
elected not to take chemistry or <strong>physics</strong>. Several vocational <strong>school</strong>s are using it
as part of their technological instruction.
The student needs no specific earlier training. The required mathematics is
reviewed at the start of the course. Algebra is taken concurrently or in the
following year, and each course reflects understanding into the other.
It was decided that the desired objectives would be met by incorporating the
following features :
374 Details of Various Projects

(a) The use of measurement equipment by the student as the principal vehicle
of instruction, through guided manipulative learning operations (M LOS),
the textbook being relegated to second place.
(b) The use of equipment that impresses the student, being real apparatus and
not a cheap substitute or a toy. Example: mass is measured using a standard
commercial balance, not by counting beads or beans.
(c) The existence of a Teacher’s Manual that teaches the teacher what is to be
done, if (as is usually the case) he has had only minimum exposure to
chemistry and <strong>physics</strong> as actually practised by the professional.
(d) A stockroom of equipment so chosen as to minimize the cost and maximize
classroom successes.
B.13.1 The QPS course
The 25 units of the QPS teaching programme can be grouped and their content
briefly described as follows:
Units Topics cooered
1-7 Fundamentals: measurement technology, closeness of measurement and accuracy,
graphing, calculation technology, exponential arithmetic, equations and
formulae; measurement of length, area, volume, mass and density.
8-1 1 Physical phenomena: force, weight; coherent systems and dimensions of units;
Archimedes’ principle, Hook’s law; work, energy, power; temperature and heat;
the phases of matter; the atom; the chemical elements.
12-16 Electrical phenomena: the electric circuit; charge, current, e.m.f., resistance,
potential; circuitsymbolism; Ohm’s law; electrical energy and power;
practical circuits; alternating current.
17-23 Chemical phenomena; fundamental chemical practices; electron structure of
chemical elements; gases and gas laws; bonds and valency; reactions and
equations; acids, bases, salts; electrolysis, electric cells, electroplating,
electrometric titration.
2&25 Waue phenomena; refraction, reflection and dispersion of light; image
formation, properties of lenses; simple harmonic motion, sinusoidal functions,
travelling and standing waves; sound waves; electromagnetic radiation.
Learning starts with specific items and progresses to generalities and conclusions.
Processes and scientific content are intermingled. The textbook supplies
connecting links, organizes that which has been observed in the classroom, and
serves as a basis for study and review. Films are not employed. When the teacher
demonstrates, it is in connection with a device the students are about to use.
Generally, three or four MLOs form the basis for each unit of instruction. The
work is sequenced so that the course content preceding any unit constitutes
preparation for that unit.
In one respect this is an instructional programme in the basic elements of
scientific communication, the elements that wil aid a person in understanding
what is presented to him in text<strong>books</strong>, technical articles and lectures. The
375 Course Development Project in Quantitative Physical Science

asics include : scientific notation, metric measurement units, slide rule work and
related calculation processes, symbolism, graphical analysis, the making of
approximations, rapid and accurate scale readings.
The project was under the direction of Dr Sherwood Githens, Department of Education,
Duke University, College Station, Durham, North Carolina 27708, US A, from whom
further information can be obtained.
The work of preparation has resulted in the production of the following materials:
(1) A sequence of 90 ‘manipulative learning operations’ (MLOs) through which the
basics of physical, thermal, electrical, chemical and wave phenomena are developed
systematically through personally-conducted observations, measurements, calculations
and analysis, (2) A set of equipment matched to permit these operations at minimum cost,
most of the equipment being commercial in type but some of it specially designed; (3) A
textbookdesigned to match the sequence of MLOs; (4) A teacher’s manual written for the
absolutely ‘green’ teacher, with apologies to those who are not so ‘green’;(5) A student’s
manual, intended for use when it is desired to have the student read the instructions instead
of receiving them verbally, in particular where self-pacing is desired; (6) Equipment lists,
suggested suppliers, information on classroom furniture, utilities, and storage facilities ;
(7) Two sets of unit quizzes and a comprehensive examination.
B.14 Scottish Physics Course
The Scottish 0-grade Certificate is equivalent in standard to the English 0-level
Examination and is taken at the same age, 16 years, although the age of entry
to secondary education in Scotland is one year later, that is at 12 years. The
Scottish programme as outlined below was written in 1962, modified in 1964 and
1969, and finally adopted by all Scottish secondary <strong>school</strong>s. The course consists
of three cycles: first cycle, 12-14 year olds; second cycle 14-16 year olds; third
cycle, 16-18 year olds. The scheme provides not only for the future physicist
but also for the future educated layman.
B.14.1 First cycle, years I and 11 (ages 12-14 years)
This can be taught as separate <strong>physics</strong>, chemistry and biology, but most Scottish
<strong>school</strong>s teach an integrated science course in this cycle. It is an introductory and
mainly observational phase. The <strong>physics</strong> content consists of sections on energy,
matter as particles, electricity and magnetism, heat flow, and ‘seeing and
hearing ’.
At this stage pupils should acquire some empirical knowledge of the world
around them, a little of the vocabulary and grammar of science, an ability to
observe objectively, an ability to solve problem situations and think scientifically,
and an awareness of the culture which is science. Furthermore, pupils wil
acquire some simple science-based practical skills and some experimental
techniques.
376 Details of Various Projects

B. 14.2 Second cycle, years ZZZ and ZV (ages 14-16 years)
In this second stage <strong>physics</strong> is taught separately from chemistry and biology. The
content involves a study of waves, Newtonian mechanics, heat energy, electron
<strong>physics</strong> and the nucleus. The course emphasizes the <strong>physics</strong> important for the
future of the educated layman. The syllabus is designed to assist teachers to encourage
pupils in developing their own attitudes of inquiry and a sympathetic
understanding of their environment. The 0-grade examination at the end of the
cycle involves the cognitive objectives discussed elsewhere in this volume (see
pages 8C84).
B.14.3 Third cycle, years V and VZ (ages 16-18 years)
In the third cycle of secondary education pupils take the higher grade <strong>physics</strong>
exam in year V at the age of 17 years. In Scotland this is the key to university
entrance. The scheme includes further work on Newtonian mechanics and electricity
(electrical measurement, capacitance, electrical oscillators) as well as
optics, spectra and atomic models.
The final year, year VI, involves a certificate which is obtained by all the
pupils presented. In this certificate of Sixth Year Studies, 50 per cent of the
marks are allocated for project work undertaken by the pupil during his last
year of study at <strong>school</strong>. The other 50 per cent are awarded on the basis of a
formal examination, the syllabus for which includes further work on mechanics,
waves, electric and magnetic fields and ax. theory, all of which incorporates a
more mathematical approach.
In the project work pupils are expected to develop the ability to extract,
interpret andclassify information (use of libraries, journals, graphs, simple
statistics, estimations of experimental uncertainties, etc.); to plan appropriate
experiments, to devise and construct and/or handle apparatus in order to tackle
the practical problem of measuring some physical quantity; finally, to present a
lucid, coherent report on their own individual experimental (project) work.
The curiculum development officer is W. Ritchie, HMI, Scottish Education Department,
St Andrew’s House, Edinburgh, UK.
Pupil work sheets are available for the course and are obtainable from Heinemann Ltd,
48 Charles Street, London W1X 8HA, UK. Apparatus lists are available from Scottish
Schools Science Equipment Research Centre, 103 Broughton Street, Edinburgh, UK.
The syllabus is obtainable from the Scottish Certificate of Education Board, 95 Nile Street,
Glasgow, UK.
377 Scottish Physics Course

C Comparative Studies
It has become very apparent from the projects which have now been developed throughout
the world that there are many different ways of approaching various topics. No one can
claim that one particular approach is necessarily ‘right’ and that the others are all wrong. It
was felt that it would be helpful to include in this volume some comparative studies, the
purpose of which is to show how a few selected topics have been given very different
treatments. The emphasis is on the difference of approach: no attempt is made to suggest
that one method is better than another.
The comparative studies have been specially written for this volume by Geoffrey W.
Dorling and the three topics chosen are:
1. Energy
2. Optics
3. Relativity
The topic of energy necessarily pervades the teaching of <strong>physics</strong> at any level in a
secondary <strong>school</strong>. Optics usually finds a place in most elementary courses, whereas
relativity is an example of a conceptually difficult topic, usually confined to the more
advanced levels in a secondary <strong>school</strong> if it is taught at all. It seemed therefore that this
selection of topics was an appropriate one for this volume.
C. 1 The concept of energy
There has for many years been a remarkable uniformity in the treatment of energy
in <strong>school</strong> <strong>physics</strong>. As with many approaches which have come in for criticism
during recent years, the traditional development reflects a rationalization of the
historical emergence of the concept without really doing justice to history.
E. Mendoza (1962) wrote :
The history of the conflict between the mechanical theory of heat and the caloric theory
has, as usually presented, all the vividness and simplicity of a cowboy film.The protagonists
are sharply divided into thb good characters (Rumford, Davy, Joule) and the bad ones
(unnamed). The action is brief but conclusive. Cannon are bored, pieces of ice rubbed
together, paddle wheels are turned, and the bad characters are humiliated.
Since this uniform traditional approach to energy is the backcloth against
which many recent teaching schemes must be seen, it is worth laying it out in
detail. The topic is usually presented through a study of forces and motion. Here
is a route diagram typical of many schemes which are to be found in text<strong>books</strong>
and courses alike.
378 Comparative Studies

1
Heat
1 1
-
Mechanical
equivalent
Gravitational
of heat
1 -
Heat as energy
Universal conservation
law
Force
Work
Energy
Kinetic
potential energy -- energy
1
Limited conservation law
Other forms of energy
Energy is frequently defined as the ‘capacity to do work’. The studies of heat and
mechanical energy are developed independently. Their relationship is shown by
an experiment to ‘measure the mechanical equivalent of heat’. This approach is
pseudo-historical. Mendoza does not criticize a historical approach but appeals
for justice. So this survey wil start by seeing how Harvard Project Physics,
which emphasizes the historical arguments throughout its course, has developed
the topic of energy.
C. 1.1 Harvard Project Physics
One chapter of the four which constitute Part 3, The Triumph of Mechanics, is
devoted to an introduction to the concept of energy. The summary in the Teachers’
Guide (Harvard Project Physics, 1969) to that chapter begins:
The concept of work, defined as the product of the force on an object and the distance the
object moves while the force is exerted on it, is interpreted as a measure of energy, transformed
from one form to another. With this interpretation expressions can be derived for
the kinetic energy, +mu2, of an object and forthe change in gravitational potential energy,
F,,,,d, of an object of weight Fgrav which moves through a verticaldistance d. Other forms
of potential energy are mentioned. If there is negligible friction the sum of the kinetic energy
and the potential energy does not change; this is the law of conservation of mechanical
energy.
After a comment on the need to define work more accurately the guide
continues :
The present-day view of heat as a form of energy was established in the nineteenth century,
partly because of knowledge of heat and work gained in the development ofthesteamengine.
The development of these engines from Savory to Watt is traced out, and then the
programme turns its attention to the work of Joule ‘who performed a variety of
experiments to show that a given amount of mechanical energy (measured, for
379 The Concept of Energy

example, in joules) is always transformed into the same amount of heat (measured,
for example, in kilocalories) ’.
Some attention is devoted to the supply of energy needed by living systems. The
social consequences of this in a world of expanding population is briefly touched
upon.
In the early nineteenth century, developments in science, engineering and philosophy contributed
to the growing conviction that all forms of energy (including heat) could be transformed
into one another and that the total amount of energy in the universe was conserved.
The newly developing science of electricity and magnetism revealed many relations
between mechanical, chemical, electrical, magnetic and heat phenomena, suggesting that
the basic ‘forces’ of nature were related.
Since steam engines were compared on the basis of how much work they could do for a
givensupply of fuel, the concept of work began to assume considerable importance. It began
to be used in general as a measure of the amount of energy transformed from one form to
another and made possible quantitative statements about energy transformations. . . .
Of a large number of scientists and philosophers who proposed in some form a law of
conservation of energy, it was von Helmholtz who most clearly asserted that any machine or
engine that does work cannot provide more energy than it obtains from some <strong>source</strong> of
energy. If the energy input to a system (in the form of work or heat) is different from the
energy output, the difference is accounted for by a change in the internal energy of the
system.
The law of conservation of energy (or the first law of thermodynamics) has become one of
the very foundation stones of <strong>physics</strong>. It is practically a certainty that no exception to the
law will ever be discovered.
Despite its historical background this development shows some markedly different
features from the traditional approach. Two are of particular importance :
(a) Work is represented as a means of measuring energy and thus as a means of
defining someparticular forms of energy. The course text says ‘The general concept
of energy is very difficult to define; in this course we shall not attempt to do
so.’ Instead the concept is allowed to emerge alongside the sense of conservation.
(b) The relationship between heat and energy is developed against a background
of the industrial developments of the nineteenth century, which are shown to have
had an important impact on scientific theories.
C. 1.2
The PSSC approach to energy
This reassessment of the relationship between work and energy has been a feature
of other recent teaching schemes. The Physical Science Study Committee’s approach
to energy strongly advocates a redrafting of the traditional approach, and
their comments have undoubtedly influenced a number of other projects. The
following summary of their views is drawn from Part 111 of the Teacher’s
Re<strong>source</strong> Book and Guide (P S S C, 1960).
The lastthree chapters of Part I11 provide a broad treatment of the concept of energy. These
chapters depart rather sharply from the standard development that has been used in many
introductory courses. For this reason it may be worthwhile to discuss briefly the general
nature of how energy is developed in these chapters.
380 Comparative Studies

C. 1.3
Importance of the energy concept. Application of the law of conservation of energy is a
powerful method for solving a broad range of problems, hence energy is one of the most
basic concepts of <strong>physics</strong>. It is therefore important for students to understand both energy
and the conservation of energy.
Omission of a definition, The text makes no attempt to give a specific short definition of
energy. There is none! Rather than beginning with a definition. a better eventual comprehension
and appreciation of the significance of the idea of energy can be achieved through
building an understanding of how the concept of energy can be applied to many phenomena.
In pursuing such a development, the text presents the following ideas :
The term energy is applied to many widely differing characteristics of the motion and
relative position of matter. A singleterm is useful because these widely varying characteristics
are all connected through a single conservation law. In order to emphasize the breadth
of the energy concept and to stress energy conservation, the text purposely avoids an oversimplified
energy definition such as the ‘capacity to do work’. Instead various forms of
energy are introduced and the convertibility of energy from one form to another is discussed.
The concept of work takes its rightful place as simply one mode of energy transfer, Work is
defined on a quantitative basis; it is then possible to formulate a quantitative description of
several forms of energy, starting from the amount of work done to produce them.
Plan ofattuck. The strategy of the text is to introduce the three forms of energy that appear:
kinetic, potential and thermal. With these three forms, it is possible to discuss the transfer
of energy from one form to another showing that the total energy is always conserved.
The Introduction then continues with an example to show the difficulties that arise
if energy is simply considered ‘the capacity to do work’, and concludes:
From even this briefsample of the many forms in which energy is manifested, it is clear that
no brief definition can give adequate feeling for the true breadth of the concept. The important
thing is to develop some feeling for the broad utility of the conservation law in dealing
with the many widely-different guises of the thing we call energy. If you can give your
students some appreciation for this idea, they will have something that is much more
powerful than a neatly packaged, but incomplete, five-word definition.
The detailed development of the topic follows the lines laid down. From an
intuitive feeling about ‘energy’ the definition of work is developed. This leads to a
detailed study of kinetic energy and potential energy. The approach to heat also
shows a wide divergence from the historical approach. In an earlier chapter in the
course, concerned with the particulate nature of matter, heat and temperature are
shown to be linked with the random motion of the particles. Now this theme is
developed in more detail. The kinetic theory of gases is placed on a quantitative
basis. Temperature is identified with the kinetic energy of the randomly moving
particles. ‘The concept of thermal energy is developed and a distinction drawn
between total thermal energy and kinetic energy of centre-of-mass motion.’
This view of heat as a form of energy isjustified by an appeal to the experiments
of James Joule. Heat flow is seen as a transfer of thermal energy from a hot body
to a cold.
Energy in the Nufield 0-letiel Physics Project
The PSSC’s programme introduces heat in energy units from the first. The
Nuffield 0-level project in <strong>physics</strong> takes a different view. In the General Introduc-
381 The Concept of Energy

tion to the Teachers’ Guides (Nuffield, 1966, vol. l), considerable attention is paid
to the approach to conservation of energy. After discussing the need to justify
some conservation laws experimentally, the guide continues :
But, above all, conservation of energy has, we feel, a double claim to experimental discussion.
First, because it is not obvious; it was not obvious to the capable physicists of the
eighteenth century. ... Second, the conservation of energy has grown to be so powerful and
useful that we now support it at any cost.
The following approach is then recommended :
We should introduce energy as something very important that we ‘get from fuel’, that does
useful jobs of work for us in raising loads etc., that can be changed into the form of heat, and
so on. In early discussions we shall probably take conservation for granted without pupils
(or even teachers) noticing the assumption; but we should not continue to do that all
through.
Three lines of attack are suggested:
(a) Ideal machines have equal input and outputs of mechanical energy.
(b) Potential energy +kinetic energy is constant in conservative systems.
(c) We have sound experimental reasons for regarding heat as a form of energy.
In this latter case, the guide goes on to say:
We are left with the great series of nineteenth-century experiments done by Joule and others
in which interchanges of electrical energy, chemical energy, thermal energy and mechanical
energy were shown with increasing certainty to support a general conservation of energy.
Although the result of each experiment was reduced to a numerical value of J, these experiments
did not just show that heat and mechanical energy are interchangeable; they compelled
a belief in conservation in a much wider variety of interchanges. We shall ask pupils
to survey that evidence, not as an arbitrarily chosen chapter in the history of science, but to
show the building of a very important part of science. The many and varied experiments
need some description, and then the converging values of J exhibit the evidence. If pupils
know beforehand that these are pieces of testimony from difficult experiments, pointing to
the guilty victim, a universal constant for J, as a symbol for conservation, they will not find
this great story confusing.
We must of course have a different unit for the thermal measurements (most of them done
with water) from that used for the mechanical measurements, until the case is proved. . . .
Therefore we shall not get rid of the calorie as a unit until after we have discussed the evidence
for general conservation of energy.
One important feature of the Nuffield 0-level <strong>physics</strong> scheme is the parallel
(rather than end-on) development of all its major themes. The particulate nature
of matter, the kinetic theory of gases, electricity, dynamics, are all major themes
developed in this way. Energy is treated as another. Thus it is separated from a
study of dynamics at the outset and identified as a concept of universal importance.
The first ideas about energy are introduced in year 1 of the course:
In our earliest discussion of energy we should refer to fuel from the beginning, rather than
by just describing the mechanical energy got out of machines or by discussing the input and
output energies for things like pulleys and levers.
382 Comparative Studies

Fuel conversion is seen to be accompanied by a change of energy from some
stored-up form to another form, and the introduction concludes with the words
‘We should include food with fuel. And we must add sunshine itself as “free fuel
from the sun ! ” ’
Work is introduced when the need to measure energy changes arises:
In this programme we propose to return to an old-fashioned use of the name ‘work’ in
<strong>physics</strong>: work calculated by multiplying force by distance as a statement of the amount of
energy transferredfrom one form to another. W e shall not use ‘work’ as a name for a type of
energy itself. We shall not use it as a rough name for mechanical energy.
Further development takes place in year 2 and a qualitative relationship
between energy and heat is observed. At the same time heat itself is studied
phenomenologically and measured in calories.
Any further development of the concept awaits a parallel development of the
behaviour of forces. Once the kinetic energy of motion has been quantified in
year 4, the conservation of mechanical energy in conservative systems is discussed.
The concurrent development of the kinetic theory of gases has already led to a
qualitative link between temperature and the energy of motion of gas molecules.
The ground is thus prepared for a detailed discussion of the experiments of Joule
and others in the nineteenth century. From this the universal law of conservation
of energy evolves. Only then is the kinetic theory of gases placed on a quantitative
basis.
C. 1.4 Energy in integrated science courses
The three approaches which we have surveyed above have aimed at giving an
understanding of the concept of energy within the context of a study of <strong>physics</strong>.
The opportunities for the development of this theme in a programme containing
<strong>physics</strong> as one component of an integrated science course are even greater. Energy
can be presented as a unifying concept of even wider application. It is thus not
surprising to find energy occupying a place as a major course theme, as it does in
the Nuffield 0-level project in <strong>physics</strong>. Of the many examples available, the
following are chosen for the variety of approach they offer.
Science for High-School Students in New South Wales. The Science for High-
School Students project* spans four fields of science, astronomy, biology,
chemistry and <strong>physics</strong>. The concept of energy is introduced within the first few
pages of the text in relation to the changes taking place in a body as its temperature
rises. The universality of application of the concept is suggested at once.
A qualitative study of heat soon follows, but it is always recognized as an aspect
of energy: ‘Energy occurs in many forms, and as you wil see in Chapter 13 there
is a distinct tendency for different forms to end up as heat in some place or other.
Energy may appear to be lost but you wil often find it has been converted to heat
in such cases.’
* Senior Science for High-School Students. The Wyndham scheme. New South Wales. Australia.
383 The Concept of Energy

The introduction to a study of the living world enlarges the theme and it is
recognized that :
A characteristic of living things is that they use energy. Some organisms use energy for
movement of parts of their body, or in motion as they move from place to place. Some other
organisms, glow worms and many deep-sea fish, produce light. In all organisms some energy
is converted to heat. You must have noticed that your body gives heat to the atmosphere.
Probably most organisms store some energy in an electrical form, while the function of
nerve and muscle cells is dependent on electrical energy.
The next few chapters will be concerned with electrical and other forms ofenergy, and how
waves carry energy. This information will be useful in understanding the basic role of energy
in life.
The following chapters lead up to a study of the forms of energy and machines.
The energy of motion is considered in detail with heat energy as one aspect of this.
Potential energy is discussed and machines are introduced as enabling man to
make more effective use of energy.
This study of motion leads to a study of forces and the topic of energy does not
return until much later in the course. By that time the student is equipped to deal
quantitatively with the topic. Mechanical work is defined and shown to be a
measure of energy transfer. Then follows a quantitative study of heat. The text
says :
. . in order to measure heat, we must first choose a unit and then, by means of a suitable
property, compare with this unit the quantity of heat to be measured. W e have learned
earlier that heat is one of the many forms that energy can take. Therefore we should expect
to measure heat by comparison with a unit of energy such as the joule used for measuring
work and energy.
Let us first, however, try to understand the difficulties encountered by earlier scientists
who, towards the end of the eighteenth century, first tried to measure heat.
We must realize that the physicists and engineers of this period thought of heat not as a
form of energy but as an entirely separate quantity. They understood very well that energy
must be expended in doing work, mechanical work, but there were no heat engines in those
days to illustrate that work could be done also by applying heat to a boiler.
It is not surprising, therefore, that these earlier scientists did not consider energy when
trying to devise a unit of heat. They thought rather of the common warming effects which
heat can produce; rise in temperature, expansion, change of state and so on. Since the
original units and method of measuring are still used today for special purposes, let us carry
out several simple experiments in order to understand theprinciples on which they are based.
Thus, while accepting heat as a form of energy, the text develops the study of
heat in an empirical manner, introducing the calorie as a unit, but stating immediately
that this is equivalent to 4.2 joules. Ultimately, the experimental evidence
for the energetic nature of heat is revealed through a discussion of the
experiments of Joule.
Earth Science Curriculum Project. Energy is also an underlying theme in a quite
different science teaching programme, the Earth Science Curriculum Project
(1967) entitled Investigating the Earth. An early chapter (chapter 6, ' Energy Flow ')
is devoted to the concept of energy, and is introduced with the words :
384 Comparative Studies

A landslide crashes down hill into the valley below. A tornado sweeps a path of destruction
as it roars through the heart of a town. A mountain glacier tears out the floor and walls of
the valley through which it flows. Ocean waves pound a grounded ship to splinters. A raging
stream cuts into its bed, laying bare the rocks beneath. Strong winds shiftsand from place to
place. Energy is acting at or near the earth’s surface in each of these examples. Energy in
many fords powers natural processes.
Changes taking place today, like changes throughout time, require energy. . . . Change is
accompanied by a flow of energy.
Nufield Secondary Science Project. A third example of a curriculum development
in which a study of energy forms a major theme is the Nuffield Secondary Science
Project. This project, which is an integrated science course for non-academic
children, is still in its development stage. The course is written in terms of eight
themes, one of which is called Harnessing Energy. In fact the concept of energy
pervades any study of science, and energy considerations occur in all the themes.
A brief survey of the development of the energy theme as presented in Harnessing
Energy can hardly do justice to the approach unless it is seen in the context of
the project’s treatment of science as a whole. In particular, the abilities of the
pupils for whom it is meant dictate that the depth of study is different from that
envisaged in almost all the other projects so far discussed. Greater emphasis is
perhaps also given to the investigational aspect of science. With these warnings
against too ready an interpretation of the content, the following summary is
presented to illustrate two aspects of this study of energy which have not been
represented in the programmes so far considered.
The study of the concept of energy is introduced to the teacher as follows:
Man’s ability to convert and utilize energy on a massive scale has completely changed and
enormously enriched his way of life. This ability has, more than any other single factor,
contributed to the development of civilized life as we live it today. One of the aims of the
work in Harnessing Energy is that the pupils should realize thisand appreciate that the ways
in which we use, control and direct natural forces have enabled us to accomplish things
which to our ancestors were merely dreams. To he able to fly, to orbit the earth, to travel
swiftly over land and sea, to extract huge quantities of material from the great depths of the
earth or under the sea, these are but a few of the benefits available when vast quantities of
energy are at our disposal.
The theme is divided into four fields of study. The first, ‘Energy in action’, gives
wide experience of energy conversion processes and shows a link between energy
and motion. The second field of study develops the idea of forces and introduces
work. This in turn leads to an investigation of man’s physical limitations and the
advantages to be gained by using machines. The third field of study is concerned
with the electrical transmission of energy. Investigations include electric motors,
simple d.c. circuits, electrical effects and a study of alternating currents. The
fourth field of study is called ‘Problems of bringing energy to bear’. Within it an
investigation is made into the relationship between heat and mechanical work and
the efficiency of fuels.
The study as a whole presents two particularly novel features:
385 The Concept of Energy

(a) The energy theme is allowed to give point to a detailed study of other branches
of <strong>physics</strong>. A study of forces and electricity, for example, comes about in an
attempt to understand energy.
(b) Considerable stress is laid on the social impact of an understanding of energy.
The importance of fuels, machines and the transmission of power to the wellbeing
of the world is seen as an important reason for their study.
East African Secondary Science Project. This latter presents a new aspect of the
study of energy. Within recent years developments in science teaching have frequently
reflected an increasing awareness of the need to relate science to society.
This is well illustrated in the <strong>physics</strong> component of the East African Secondary
Science Project.
The material within this presentation owes much to the Nuffield 0-level teaching
project, but its development differs significantly from the Nuffield course in
two important ways.
(a) The theme of energy is taken as a major course component and is enlarged
upon. Energy itself becomes one of the endpoints.
(b) The idea of energy is stranger to pupils growing up in an African environment
than it would be to those who live in highly industrialized communities. Thus
ideas such as heat as a form of energy have to be introduced cautiously.
The topic is introduced into year 2 of the course and is developed in this and the
following two years of the four-year course. Greater attention is however given to
the variety of machines than in the Nuffield course. ,It is after the conservation of
energy has been established in year 3 that the theme is extended beyond the limits
of the Nuffield scheme. Year 3 continues with a brief discussion of simple heat
engines and the internal-combustion engine.
After further studies in year 4 of electricity, radioactivity and the atomicity of
matter the topic of energy is picked up again. The two final sections of the course
are entitled ‘Atomic energy’ and ‘The importance of energy to society’. The topic
of atomic energy is concerned with the nucleus as a <strong>source</strong> of energy. Nuclear
fission and chain reactions are given a simple treatment and applied to atomic
bombs and nuclear power stations. The final topic is introduced in the ‘Introductory
Statement’ with these words:
Having, over the course of nearly four years, let pupils learn something of the most important
concepts of <strong>physics</strong>, it is appropriate finally to make them aware of the value to
society of the work of physicists. The previous section shows the importance of ideas about
the structure of matter, related to both economic development and social problems. One
can then usefully discuss the importance of energy re<strong>source</strong>s inthe same way . . . man needs
energy primarily to maintain life.Pupils can work out how many joules are needed daily to
sustain the population of theircountry.
Apart from simple needs for cooking and lighting, modern society needs other readily
available forms of energy for transport, industrialization, etc. Discuss present <strong>source</strong>s of
energy, and the convenience of transforming other forms into electricalenergy for distribution
and ready availability.
386 Comparative Studies

The transformation of solar energy by crops and fossil fuels is discussed. Particular
attention is paid to the possibility of other energy re<strong>source</strong>s. Hydroelectricity,
the direct use of solar energy and geothermal energy receive attention in the
light of their special possibilities in East Africa. Finally, the introductory note
concludes : ‘ By concluding the course in this way for all students it is hoped that
even those not going on with <strong>physics</strong> wil see its value to modern society.’
C. 1.5 Conclusion
There have been many new approaches to the teaching of energy in recent years.
New approaches to such a fundamental and yet sophisticated idea are still evolving
and the newest work is not without its critics. This survey began by referring to
an article criticizing an approach to heat and energy prevalent in the early 1960s.
In September 1970, M. W. Zemansky (1970) was still able to write: ‘The concept
of thermal energy is by all odds the most obscure, the most mysterious, and the
most ambiguous term employed by writers of elementary <strong>physics</strong> and by chemists.’
C.2 Optics
C.2.1 Introduction
A study of the properties of light has a part to play in almost all <strong>physics</strong>-teaching
schemes at both elementary and advanced levels. The reasons that have been advanced
for its inclusion are probably more diverse than for any other topic.
There is no doubt that the nature of light energy serves as a splendid example of
model-building in <strong>physics</strong>. In the first instance, the properties of light can be
shown to be consistent with a wave-like, rather than a particle-like, transfer of
energy. At a later stage, although still within the scope of <strong>school</strong> programmes, this
model can be shown to need modifying to account for the behaviour of light in
such things as the photoelectric effect. The PS SC treatment in the USA, as well
as the Nuffield project in the UK strongly emphasize this line of development.
In Unesco’s I B E C C study in Latin America a study of the behaviour of light is
used to illustrate the entire armoury of <strong>physics</strong> methodology, in so far as it is appropriate
for a <strong>school</strong> course, from the correct treatment of experiment and
meaning of ‘error’ to the understanding of processes such as the making of
generalizations and the building of models.
At a rather more advanced level light may be a convenient experimental area
for exploring behaviour common to the whole of the electromagnetic spectrum.
Examples of this are to be found in the treatment of diffraction and quantum ideas
in the Nuffield A-level Physics Project, as well as in the PSSC course and in
Harvard Project Physics.
Some advocate a study of the behaviour of light because an understanding of it
has important bearings on many technical developments which people wil experience
in their everyday lives. The camera, the telescope and spectacles are all
applications of the behaviour of light applied to lenses. Such technical developments
strongly influence work in other fields, the most obvious example of which
387 Optics

is the microscope. A thorough acquaintance with this instrument demands a
knowledge of lens behaviour at the more elementary level and of diffraction theory
at the more advanced.
Finally there is the argument which has long been used to justify a strongly
traditional development of optics through the laws of reflection and refraction. A
detailed approach to geometrical optics by this route provides one of the few
glimpses, at an elementary level, of the way <strong>physics</strong> can weave a fabric of deduction
and application from one or two basic laws.
The account that follows wil outline some recent teaching approaches to optics
in a few specific projects. It is hoped that through these outlines the reader wil be
able to see both the diversities and similarities of modern approaches to this topic.
C.2.2 The treatment in Nufield 0-level Physics Project
The background against which this project developed its teaching of optics
(intended for pupils age 13-14 years) is laid out in the introduction to the year 3
Teachers’ Guide :
In the customary approach to the teaching of geometrical optics one starts with the properties
of rays of light, which are conceived of either ideally as straight lines along which
light travels or, more realistically,as narrow straight pencils of light, and one states three
groups of general laws, extracted from experiment; straight-line propagation in a uniform
medium, laws of reflection, laws of refraction. Then one derives from these laws the properties
of image formation by lenses and mirrors. In doing that one defines the image of a point
as that point to which the rays from an object converge, or from which they appear to
diverge, after reflection, refraction, etc. The image is assumed to be perfect, but the restrictions
which near perfection would require are seldom mentioned.
In the experimental background of that treatment one asks pupils to trace rays to and
from a plane mirror or through a glass block, and one sometimes gives demonstrations of
angle relations with a Hart1 disc. Then pupils test the predicted object-and-image relationships
by experiment. To many a pupil, however, these experiments do not appear as tests of a
relationship, but are simply measurements of ‘ the focal length’. The general action of a lens
becomes lost in worship of a particular image point, the focus.
Pupils who findthe algebra or arithmetic of formulae too hard are offered a simple construction,
using ‘undeviated rays’ and the property of ‘ parallel rays passing through the
focus’.
Only afterall that do pupils meet optical instruments, although those should seem to most
<strong>school</strong> children the essential matter of optics.
The Teachers’ Guide then points out the difficulties felt to be inherent in this
approach and says :
Many never see that they (thepupils) have built up from fundamental laws a magnificent
explanation of the working of lenses and mirrors, nor feel that they know all the better for
theirstudies how optical instruments work. Few emerge from <strong>school</strong> able tofocus a telescope
or microscope easilyand comfortably.
The Teachers’ Guide goes on to suggest a different approach:
If, instead, we were to startwith empirical knowledge of rays and images we should feelour
approach less‘fundamental’ but more realistic.We should reallybe offering young pupils a
388 Comparative Studies

start that is equally well based on experiment and we should be able to deal with optical
instruments earlier and in a way which would seem more direct. The only great loss would
be that we should not have the laws of reflection ahd refraction so early or make them so
prominent in our collection of great general laws; and that is a loss, because we want pupils
to see the part played by general laws in the structure of science. Nevertheless, we shall
follow in this programme a different approach, a treatment in terms of images which has
been tried before and gives pupils more confidence and skill with optical instruments.
The suggested programme starts with a sequence of brief demonstrations of
some of the properties of light, rectilinear propagation, reflection and refraction.
Pupils’ explorations start with a pinhole camera. This is soon converted to a lens
camera and pupils learn the action of a lens as something that ‘bends the rays that
come from a bright point and makes them all pass through another bright point
that we call the image ’.They gain acquaintance with this property of a lens through
a series of experiments. The focus becomes simply the place where the image of a
distant object is found.

Virtual images are introduced but are not stressed; the concept is recognized as
being difficult. But sufficient experience has now been gained for the pupils to construct
a simple telescope which ‘should just be used for looking at things’.
Attention now turns to a more detailed exploration of lens behaviour using ‘ ray
streaks’ and cylindrical lenses. Particular attention is now given to the subject of
virtual images. Ultimately the apparatus can be used to set up models of the way
light passes through optical instruments forming images.
The telescope and microscope are now treated more seriously, and simple
experiments are performed on estimating their magnifying power. These experiments
are designed to encourage a correct ‘two-eyed’ use of optical instruments
and not to justify any theoretical descriptions.
The eye is treated as an optical instrument and given detailed consideration.
Teachers are encouraged to provide cattle eyes for dissection, and a number of
models are used.
Only after this does the programme turn, briefly, to what it calls ‘formal’ optics.
Here some attention is given to ray diagrams and lens formulae.
One noteworthy aspect of this programme is the coherent set of apparatus
which has been produced for pupil experimentation. Lenses, which are described
in terms of theirpowers rather than their focal lengths, have been manufactured so
that pupil experiments suffer as little as possible from inadequate components.
The +7 dioptre lenses used in the early stages are just of the right focal length to
give an image on the back of the pinhole camera. The + 23 dioptre and a + 14
dioptre lenses used as objective and eyepiece in the simple telescope are appropriately
of large and small diameter and really do provide obvious magnification.
The cylindrical lenses used in the ray-streaks kit match the lenses already used,
as the major component is a +7 dioptre lens. A set of lenses used in conjunction
with a five-litre water-filled flask provide good demonstrations of long and short
sight.
The remainder of the work on light is concerned with ‘ Behaviour and Theories’.
The Teachers’ Guide summarizes this section in the following words :
Pupils have gained a foundation of acquaintance with waves and light-rays. At this point,
the proper way to build on that, with a good group of pupils, is to sum up ray-behaviour in
laws (treated briefly, stated informally), then raise the question of a ‘theory’ of light. In
discussing theory, we should draw on our laws for rays and on pupils’ knowledge of waves
from ripple-tank experiments. W e may show a model of refraction, and perhaps even
describe a ‘crucial’ measurement of the speed of light. Then we show diffraction and interference,
of both water ripples and light; and the balance swings in favour of light waves. W e
should end with a gentle warning against accepting a theory too firmly.
There is a return to these ideas in year 5 of the course when the wavelength of
light is measured in a class experiment, and the diffraction grating is used. Photon
behaviour is taught largely by the use of films.The approach at this stage closely
resembles that of P S S C, described below. The Nuffield course uses the PS S C
films in the work on photons.
The Nuffield Foundation’s programme in optics serves two major aims: (a) to
give a useful understanding of the behaviour of lenses and their application to
390 Comparative Studies

optical instruments and (b) to build a model which wil serve to explain the
behaviour of light, as one example of the building-up and subsequent modification
of a theory. In the PS SC project these two aims are clearly visible although
the balance swings in favour of (b).
C.2.3 The PSSC’sprogramme in optics
A study in optics features prominently in the PS SC’s course in <strong>physics</strong>. After the
introductory work contained in the first of the four parts into which the scheme is
divided, optics and wave motion occupies all of Part 11. The reasons for this
choice are outlined in the introduction to the Teachers’ Re<strong>source</strong> Book and Guide
to Part IZ.
The choice of lightas the first fieldof <strong>physics</strong> to be examined in detail has advantages. Much
of the subject can be learned by the students from laboratory work that is stimulating and
yet does not require much experimental maturity or sophisticated apparatus. With light we
can start with simple phenomena and progress to rather subtle ideas about waves, thus
bringing the student to an awareness of the nature of waves before delving into the mechanics
of particles in Part 111. Since most of us have better intuitive ideas about particle behaviour
than about wave characteristics, thissequence should cause students to be more responsive
to the ideas in Part IV that matter particles are in some degree wave-like. Finally, the study
of light provides an especially effectivecontext for considering. in parallelwith the characteristicsof
light, how a physical theory is developed.
The optics and waves section of the course is divided into nine chapters. The
first four ‘derive the principles of reflection and refraction from observation and
experiment in the laboratory and from the analysis of experiments in the text. The
application of these principles in lenses and simple optical instruments is shown.’
The introductory chapter to this subsection is concerned with a wide range of
physical properties. Light <strong>source</strong>s lead to colour transparency and reflection.
Light detectors other than the eye lead to a recognition of invisible radiations
associated with light <strong>source</strong>s. Straight-line propagation is shown to be a good
approximation to the truth, but diffraction is also introduced at this stage. The
chapter closes with a discussion of Rermer’s measurement of the speed of light.
The next chapter concerns itself with reflection and images. Curved, as well as
plane, mirrors are considered, but the ‘image’ concept is introduced by way of the
virtual image in a plane mirror. An analysis of shadow formation serves to introduce
ray-tracing techniques and this is then applied throughout the remaining
study of geometrical optics.
Real images arise in an investigation of the properties of parabolic mirrors, and
their application to searchlights and astronomical telescopes is discussed.
The application of geometrical principles to ray diagrams leads to some simple
formulae. The concept of the focus is an important one in both the study of
mirrors and lenses in this development, as the course takes the somewhat unusual
step of using the Newtonian formula
Si& = f’
throughout. (Si and So are the respective distances of image and object from the
391 Optics

focal point.) This formula has a clear benefit in elementary work, as no ‘ sign’ convention
is involved in it.
The last two chapters are concerned with refraction, lenses and optical instruments.
Snell’s law is developed quantitatively (unlike the Nuffield Foundation’s
course) and the property of lenses emerges through the commonly-used route of
prism behaviour. Lens behaviour largely concentrates on the converging lens and
the focal length is related to the ‘lens-maker’s’ formula
(b, d,)
1
- = (n-1) -+f
(whether RI or R, are both positive is decided by asking whether or not the two
curved surfaces ‘help each other’).
The subsection ends with a consideration of the camera, projector, eye, telescope
and microscope, and some attention is paid to their limitations.
The development of geometrical optics within this programme has a more
familiar appearance to those of us who have learnt our optics along traditional
lines than the Nuffield Foundation’s programme has. A possible reason is not
hard to find. The P S S C’s programme in geometrical optics has the primary aim
of introducing the Observational evidence upon which the models for light are
built. It is a secondary aim to show how some of these observed properties have
been turned to useful account in telescopes, etc. Thus the development is firmly
based around the laws of light behaviour from the very first.
It is on this observational evidence of the properties of light that the remaining
study of this section of the course is based.
An investigation into a particle model for light is introduced with the words:
The central purpose of this chapter is to give students an idea of what a physical model is,
how it must be tested, and to indicate both the usefulness and limitations of a model.
Perhaps more important, but harder to express (and teach), is the spirit of searching for
deeper understanding and seeing a little of the adventure and challenge in developing a
physical theory.
The model is shown to provide a satisfactory explanation of many properties of
light. It is shown to fail however in its interpretation of refraction, requiring light
to travel faster in the more dense medium.
The following two chapters introduce the properties of waves and show that
these have properties in common with the behaviour of light. A study of interference
phenomena then follows. It is introduced by this extract from the teachers’
guide :
Thus far, the wave model oflight agrees with the characteristics of light that were studied
earlier. Does the wave model make any predictions, the counterpart of which we may not
have seen in our previous experiments with light? The superposition of waves in one dimension
showed that when waves passed through each other, regions of complete cancellation,
nodes, were produced. Do the two-dimensional waves of the ripple tank similarly show
interference ?
The last chapter looks at interference effects produced by light. It was the PS SC
scheme which first showed how easily these effects could be seen by using micro-
392 Comparative Studies

scope slides coated with colloidal graphite in which two closely-spaced lines have
been drawn.
lamp
Figure 21
slits
eve
The interference bands fall on the retinal image of the filament lamp and are seen
as though superimposed over it. While such experiments can be used with the
older. more mature students for whom the PSSC scheme is intended, there are
difficulties in getting younger pupils to realise that the interference bands are not
really across the filament. Thus the Nuffield Foundation’s 0-level scheme
modifies this experiment so that the fringes are projected on to a screen.
lamp
Figure 22
slits
screen
In both schemes the experiments serve to give added credence to the wave model,
and a typical wavelength for light is measured. In the P S S C scheme thin-film
interference and diffraction effects are further analysed. In the Nuffield 0-level
scheme some demonstrations of diffraction are suggested for year 5, but a more
detailed account is postponed to the subsequent Nuffield A-level course.
At the end of both P S S C and Nuffield 0-level schemes the wave model is itself
questioned. The photoelectric effect is explored through the medium of experiment
and film,and a recognition is achieved of the need of a dual wave-particle
model to fully describe the properties of light. Again, differences between the two
schemes are largely ones of depth of treatment. PS SC analyses the photoelectric
effect in sufficient detail to derive a value for Planck’s constant. Such detailed
393 Optics

analysis is a prominent feature of the Nuffield A-level <strong>physics</strong> scheme, where its
discussion is more appropriate to the age and maturity of the students.
The Nuffield programme in optics is designed with two aims in view. The first
section concentrates on giving an understanding of optical instruments, recognizing
the way the behaviour of light has been turned to good effect in day-to-day life.
The second section builds a model for light as a good example of the moddbuilding
process in <strong>physics</strong> and as a precursor to an eventual wave-particle model
for matter. The two sections are almost independent. The geometrical optics of
the first section is little used in the model-building ideas of the second.
The same division of aims is seen in the P S S C scheme, with a more decided
emphasis on the study of optics as a basis for building a model for light.
A study of geometrical optics is thus only essential for gaining an understanding
of optical instruments and does not contribute much to the remainder of the
work in optics. The subject of geometrical optics is not taken up again anywhere in
either of these two courses.
Thus if a course in <strong>physics</strong> wishes to emphasize, as a major aim, the acquirement
of an understanding of <strong>physics</strong> and the nature of physical inquiry, then a
prolonged investigation into the ramifications of geometrical optics becomes a
by-way which can be conveniently omitted in favour of other topics with a more
direct bearing on physical theory as a whole.
C.2.4 Harvard Project Physics
Work on optics occupies the first chapter of Unit 4 of this six-unit course. The
title of the unit, Light and Electromagnetism immediately gives context to the
study of optics in this course.
The Teacher’s Guide to the chapter states:
Optics is a large subject, and only a small part of it is covered in thiscourse. Roughly speaking,
we have omitted almost all of geometricel optics, on the grounds that both particle and
wave models for light give equivalent predictions so these phenomena cannot be used to
distinguish between them. Instead, we concentrate on physical optics, interference, diffraction,
polarization, and look for phenomena that can be used to test theories of light. If you
want to spend extra time on lenses and mirrors, be sure that there is some payoff from the
viewpoint of added student interest and motivation since geometrical optics is not needed
for anything elsein this course.
The text opens with the question ‘What is light ?’ and establishes the theme of
the chapter with a second question ‘How appropriate is a wave model in explaining
the observed behaviour of light?’
Evidence for the straight-line propagation of light and its finite speed are discussed
against an historical background. The properties of reflection and refraction
are observed and Newton’s explanation in terms of a particle model is
examined. The fact that light travels more slowly in the medium of higher refractive
index is recognized as being ‘generally regarded as driving the last nail in the
coffin of the particle theory’.
Young’s observations of the interference of light and Fresnel’s wave theory are
produced as the further evidence which confirmed the validity of the theory.
394 Comparative Studies

Newton’s theory of colours is contrasted with some other theories. Finally the
wave description of colour is shown to provide an explanation of the otherwise
unexplained blue colour of the sky. A brief study of polarization adds detail to the
wave model, and the chapter concludes with an introduction to the problem set by
a ‘light medium’ or ‘ether’:‘Students should leave this chapter with the impression
that the wave model explains the properties of light rather well.yet something
may go wrong if one tries to think of the waves as motions of a real physical
medium ....’
The remaining three chapters of the unit are concerned with electrical phenomena
and electromagnetic waves. The identity between the speed and properties
of both electromagnetic and light waves suggest that light ‘waves’ are electromagnetic
in origm.
The validity of the wave model of light is not questioned until the second chapter
of the next unit, Unit 5, entitled Models of the Atom. Here, observations on the
photoelectric effect are shown to be incapable of explanation on the basis of the
nineteenth century view of an electromagnetic wave.
The experimental results could not be explained on the basis of the classical electromagnetic
theory of light. There was no way in which a very low-intensity train of light waves spread
out over a large number of atoms could, in a very short time interval, concentrate enough
energy on one electron to knock the electron out of the metal.
A particle (photon) model is invoked and light is shown to need both wave and
particle models for a full description of its properties.
This approach to light, in keeping with the course as a whole. emphasizes the
historical development of theories. A study of the properties of waves precedes
this study of light, as in the Nuffield project. In the PS S C scheme, a study of the
properties of waves is engendered by the failure of the Newtonian particle model.
Both the Nuffield and the PSSC’s schemes advance the Newtonian particle
model as a plausible hypothesis. eventually found wanting. In the Harvard
Project Physics approach the Newtonian particle model is never advanced as a
serious contender for a place as a model for light although its successes are discussed.
While the framework of the approach is historical, each important point
of experimental observation is illustrated in either a sequence of experiments for
the students or by the use of film.
(2.2.5 Uiiesco-IBE CC Pilot Project
Finally in this short survey of some recent innovations in the teaching of optics
we will look at the Unesco Pilot Project on the teaching of <strong>physics</strong>, developed in
South America. In all the previous projects discussed the emphasis has been on
the part a study of optics can play in an education in <strong>physics</strong>. In this project an
education in <strong>physics</strong> is advanced throiigli a study of optics. Thus a study of the
teaching of optics in the IBECC project is a study of the teaching of <strong>physics</strong>.
A summary of this unique project would hardly do it justice in the short space
available. The following extracts from the English version of the introduction
may serve to state the reasons for the choice of this topic on which to base a
395 Optics

<strong>physics</strong> course, as well as to show its aims and some indication of its contents. We
may also be able to see the extent to which it is related to other recent approaches
to optics already discussed. In the opening to the general outline of the Pilot
Project, the Director and Assistant Director write as follows :
The Unesco Pilot Project on the teaching of <strong>physics</strong> was initiated on 8 July 1963 in Sao
Paulo, Brazil. ... The objectives of the project have been to explore new methods and techniques
for the teaching of <strong>physics</strong> in Latin America and to train University staffat teachertraining
institutions in the development, production and application of these techniques. ..
The topic chosen for this course, ‘The Physics of Light’, is one of the important topics of
modem <strong>physics</strong>. It is also a topic which is ideal as an introduction to an experimental <strong>physics</strong>
course and which lends itself to illustrate most of the important aspects and principles of
<strong>physics</strong>: the fundamental roleof experiment, the nature of physical laws, the use of theory
for summarizing and predicting, the close connection between various branches of <strong>physics</strong>,
and the limitations of simple and everyday concepts in accounting for complex physical
phenomena.
The most important component of any <strong>physics</strong> course is the laboratory experiments,
which should be performed by the students themselves. For this, simple and inexpensive
equipment is needed; and one of the main efforts of the project participants has been the
development of such equipment. ...
This concentration on a single topic to exemplify the process of physical inquiry
is not the only unusual feature of the pilot project. The introduction continues:
The introduction of experimentation in the oversized classes characteristic of regions with
teacher shortage poses severe problems of instruction. Nor is the increasing number of
students coming to <strong>school</strong> adequately compensated by increasing numbers of teachers. For
this reason the development of self-instructional materials has become an urgent necessity.
There are, in addition, many inherent advantages in the use of a self-instructional, or programmed
instruction text. It ensures an active attitude of the student during his study, gives
him immediate confirmation of his comprehension of the subject and allows him to follow
his own rate of study . . .. The text for the ‘Physics of Light’ course has therefore been
developed by the project participants according to the technique of programmed instruction.
...
The question of the value or otherwise of programming involves other factors
not relevant to this comparative study and it is not therefore appropriate to discuss
this here.
Further on in their introductory memorandum the course directors develop
the objectives they seek in a course of <strong>physics</strong> education. They suggest that knowledge
of ‘ bare facts’ is the least important of all objectives and that ‘ knowledge of
the methods by which factual information is obtained is much more important ’.
They specify the need to understand the role of experimentation and the role of
theory in relation to it; the technique of obtaining quantitative information from
experiments and the use of models to predict results of new experiments. They
go on to say:
As long as the above objectives are sought, it is of little importance which area of <strong>physics</strong> is
treated in a course. The <strong>physics</strong> of light is, however, one of the most important and exciting
topics of modern <strong>physics</strong>. It serves to illustrate, as well, the close relation between different
branches of <strong>physics</strong>, which is itselfa valuable objective. In the ‘Physics of Light’ course, not
396 Comparative Studies

only properties oflight are studied; properties of particles and waves, electricity and magnetism,
heat radiation, gamma rays and photochemical reactions are also investigated.
An important objective in science teaching is to show the connections between the science
taught at <strong>school</strong> and the wonders of nature and everyday life. This objective is best obtained
by a good choice of the examples for the teaching of concepts. Radio, radar, artificialsatellites.X-rays,
etc., are well known phenomena of the modem world which are used in Unit 4
of the course.
The relationship of the ideas behind this scheme with the place accorded to
optics in other recent teaching schemes is noted.
It has further been recognized (by the P S SC group at M IT) that properties of light constitute
a much better topic for the initiationof a <strong>physics</strong> course than the conventional topic
of ‘ mechanics ’.
The programmed course consists of five units. These are accompanied by
several kits of materials for experiments to be undertaken by the students. A
sequence of film loops and television programmes are also integrated into the
course. The following account gives an indication of the content of each of the
units.
Unit 0 is concerned with the analysis of experiments and in particular with the use
and interpretation of graphs. As an example, students do an experiment to
analyse the motion of a pendulum.
Unit 1 is concerned with the fundamental properties of light. Through a number
of experiments, the student is led to explore the properties of straight-line propagation,
regular reflection, refraction, image formation and colour. The laws of
reflection and refraction are developed quantitatively.
Unit 2 considers in detail a particle model for light. The behaviour of particles is
shown to be quantitatively analogous to the behaviour of light as far as reflection
and refraction are concerned. The model is shown to predict an inverse-square
law for light propagation and this is tested in detail. It is shown however that the
model’s prediction for the change in the speed of light on refraction cannot be
sustained in practice and the model is finally abandoned. The development of this
model is allowed to throw up a number of general issues such as that of generalizing
from particular results. That the particle model is allowed to make first a
verifiable prediction before being overthrown by its incorrect predictions about
the speed of light on refraction is a particular feature of this scheme.
Unit 3 develops the wave model for light and is the longest of all the units. The
properties of waves are developed using strings and ripple tanks. Their properties
are compared with those of light. Diffraction and interference are studied and a
wavelength for red and blue light is measured.
Unit 4 deals with electromagnetic waves. This develops the need for some simple
electricity (just as it did in the Harvard Project Physics). The identity of light and
electromagnetic waves is suggested by the equality of their speeds in a vacuum.
The idea of the electromagnetic spectrum is developed and other radiations are
introduced.
397 Optics

Finally the observations on the photoelectric effect show that: ‘Neither a
simple particle nor a simple wave model sufficed to summarize all the behaviour of
light. Light as a phenomenon is too complex for its behaviour to be summarized in
such crude models as particles or waves, even though these models have been
shown to be very useful for discussing certain types of light phenomena.’
C. 2.6 Conclusion
These examples taken from the Nuffield Foundation, PSSC, Harvard and
Unesco-I B E C C projects may serve to illustrate the number of ways in which the
study of optics has been treated in recent <strong>physics</strong> teaching schemes. Perhaps of all
studies, optics demonstrates the way the content of a course can be dictated by its
objectives.
C.3
The special theory of relativity
C.3.1 Introduction
Einstein’s special theory of relativity, first published in Annalen Der Physic in
1905, has had an overwhelming influence on physical ideas during the twentieth
century. However, the conceptual difficulties of its origins and foundations and
the mathematical sophistication often demanded in understanding its consequential
influence, have restricted until recently its introduction into an education in
<strong>physics</strong> to the later stages of a university degree course.
Many actively engaged in teaching <strong>physics</strong> have argued for the inclusion of
some work on the special theory at a much earlier stage. J. Rekveld (whose approach
to relativity we shall mention later) puts forward several arguments for
the inclusion of some relativity in secondary-<strong>school</strong> courses in his chapter in
Te‘aching Physics Toduy (Rekveld, 1965).
During the past ten years there have been several successful attempts at presenting
the special theory in a way which, while acceptable to the less mature physicist,
still does justice to its concepts and consequences. In particular, all these attempts
have implicitly recognized Eric Rogers’s dictum in Physicsfor the Inquiring Mind
(Rogers, 1960): ‘Since relativity is a piece of mathematics, popular accounts that
try to explain it without mathematics are almost certain to fail.’ Thus one of their
problems has been to present the mathematical aspects in an intelligible way. In
this they are to be distinguished from the many ‘popular’ accounts written for a
lay audience.
The difficulties which have faced such innovators is made clear when we recall
Einstein’s original assertion of the principle of relativity. Conceptual difficulties
abound and yet it remains at the heart of relativity theory.
After mentioning certain apparent anomalies in physical observations made on
the electromagnetic field he went on to say (Einstein, 1923):
Examples of this sort, together with the unsuccessful attempts to discover any motion of the
Earth relativelyto the ‘light medium’, suggest that the phenomena of electrodynamics as
well as of mechanics possess no properties corresponding to the idea of absolute rest. They
suggest rather that, as has already been shown to the first order of small quantities, the laws
398 Comparative Studies

of electrodynamics and optics will be valid for all frames of reference for which the equations
of mechanics hold good. We will raise this conjecture (the purport of which wil hereafter
be called the ‘principle of relativity’) to the status of a postulate, and also introduce
another postulate, which is only apparently irreconcilable with the former, namely, that
light is always propagated in empty space with a definite velocity c, which is independent of
the state of motion of the emitting body.
This statement, together with his own development, dictated a fairly uniform
teaching approach over the succeeding fifty years. The following sequence. typical
of these presentations, is laid out in diagrammatic form as all the newer presentations
have either been closely related to this or have attempted to alleviate the
difficulties inherent in it.
Galilean relativity
I
Einstein’s relativity
df
relativity of time
1
‘ether drift’ controversy
Michelson-Morley
experiment
i
(Fitzgerald contraction)
1
electromagnetic variation of mass velocity length contraction
theory
transformation
force and
kinetic energy
I
4,
E = mc2
Dynamics
1
1
time dilation
twin paradox
Kinematics
It can be seen that the problem of presenting the theory as part of a general
education in <strong>physics</strong> can be classified under two broad headings.
(a) Showing that Einstein’s principle of relativity is a reasonable description of
physical behaviour.
(b) Showing the consequences of this principle for our ideas of the measurement
of mass, length and time.
399 The Special Theory of Relativity

Recently there have been ,several different and successful approaches to both
these problems. This section wil confine itself to just a few noteworthy examples
to illustrate some of the different presentations which have evolved over the past
ten years. The examples chosen are a sample only and are not to be thought of as a
complete survey of the field.
C.3.2 Various methods of establishing Einstein’s principle of relativity and the
invariance of the speed of light
Recent proposed developments of the theory at a level suitable for introductory
courses have fallen very markedly into two camps. There is on the one side acareful
simplification of the traditional approach already outlined, which discusses the
essence of the ether-drift controversy, leading ultimately to the Michelson-
Morley experiment and the invariance of the speed of light. From this experimental
fact the principle of relativity is developed.
On the other side are those accounts which feel that the ether-drift controversy
is a piece of interesting history quite unnecessary to an understanding of the
theoryper se. W e wil consider briefly some examples of each approach.
The ether-drift approach. The PSSC start their account in the Advanced Topics
Supplement as follows (PSSC, 1966):
The waves on a coil spring, water waves, sound waves, and the ‘starting wave’ in a line of
cars at a traffic light all propagate in a medium. There is always something, the shape of
which moves. It is natural to ask what is the medium in which light waves travel. Or, to put
it differently, what is it that is waving in a light wave?
This question puzzled many physicists of the nineteenth century and they devised various
experiments in order to prove the presence of the light-carrying medium, the ‘ether’. They
realized that the ether must be very different from all other wave-carrying media because it
apparently is present even in the highest vacuum as well as in transparent materials. It is
therefore unlikely that the ether is a form of matter with such properties as a chemical composition,
density and the like. The physicists of the nineteenth century did not look for these
material properties but asked themselves the following fundamental question:
The ether occupies all space out to the farthest stars. The Earth moves through this space,
rotating on its axis and around the sun. H ow does the ether move with respect to the Earth?
Does the ether follow the Earth’s motion, being therefore at rest with respect to the Earth, or
is the ether at rest with respect to the sun and other fixed stars? In the latter case it is obvious
that the ether would move with respect to the Earth.
After indicating that experimental evidence exists to contradict any assumption
that the ether is at rest with respect to the earth, the P S S C course sets out to show
how physicists attempted to measure an ether-drift velocity. The discussion is
centred around the Michelson-Morley experiment. Some of the difficulties inherent
in a thorough understanding of this experiment are relieved by the introduction
of a laboratory experiment utilizing an interference pattern formed by light
passing partly through water.
An account of relativity theory in Senior Science for High School Students
in New South Wales follows a similar introductory pattern. After a short account
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of Rermer’s measurement of the speed of light the ‘ether drift’ question is introduced
with the same problem as that posed by the P S S C.
. . . the question was asked ‘What is it that carries the waves?’ Nineteenth-century physicists
answered this in what to us now may appear to be a strange way. They suggested that the
whole of space, empty space, was filledwith some ‘stuff they called the ether. They assumed
that it had no physical properties by which it could be detected so that it appeared to us precisely
as a vacuum. Its only property was that it carried electromagnetic radiation and that
the radiation moved through it at the speed of light, c. Despite the fact that the ether was
assumed to have no detectable properties, it was realized that if it existed at all it should
betray its presence in one special circumstance. To understand this it wil be necessary to
consider two simple analogies.
The two analogies discussed are the time taken for a boat to travel a measured
distance up and down a flowing stream and the time for the boat to make a
journey of the same distance across the flow. This analogy to the Michelson and
Morley measurements was also proposed by H. Bondi (1965), and by an arithmetical
method it avoids some of the difficult algebra associated with an analysis
of this experiment.
Consequent upon the null result for an ether-drift velocity obtained by
Michelson and Morley. Einstein’s solution is proposed.
In 1905 Einstein suggested that it was absurd to introduce the concept of the ether just
because we think that light in a vacuum should behave like sound in the atmosphere. He
took as a fundamental experimental fact that the speed of light iiz a oacuzun is always constant,
no matter how the obseroer moves. On the basis of this ‘law of light’ he was able to
present a completely new and different picture of space and time.
‘Linear’ approaches. Writing under the heading ‘ Relativity’ in <strong>Teaching</strong> Physics
Today J. Rekveld (1965) took quite a different view of the way relativity theory
should be introduced at an elementary level. He says :
Although a short historical sketch has been added to thispaper the author does not intend
to propagate the opinion that relativitytheory should necessarily be preceded by a more or
less complete survey of the pertinent struggle in the last century that led to Einstein’s theory.
To understand what was going on in connection with the theory of an all-pervading ether is
in itselfa difficultenterprise,
It is true of course that a discussion of the historical process motivates the need for a new
and revolutionary theory, but it does not in the least prepare or promote an understanding
of relativity theory proper.
Therefore an introductory course of relativity, taught in the second half of the twentieth
century with only a limited amount of time at one’s disposal, might better be started directly
from the fundamentals of Einstein’s theory, leaving historical development perhaps to a
more advanced course.
He then proposes that an account of the theory should be preceded by a careful
look at Galilean relativity which calls
. . . the attention of our students explicitly to the importance of the notion of ‘frame of
reference’ and makes them familiar with the expression: inertialframe. It leads toarestricted
principle of invariancy, namely the laws of mechanics. It teaches students the simple trans-
401 The Special Theory of Relativity

formations enabling them to go from one inertial system to another and paves the way for
the more complicated transformation equations in Einstein’s theory.
This introduction leads on to a discussion of how we usually determine velocities
relative to different inertial frames, and he continues:
We know that our Earth is moving round the sun in a nearly circular path with a velocity of
30 km s- ’. It moves in different directions in different parts of the year. We might take this
opportunity to investigate the dependence of the velocity of light on the direction of the
earth’s motion.
We can refer here to the famous experiment performed by Michelson and Morley for the
first time in 1887. Because of the roleof an interference effect it does not seem likely that we
could explain this experiment on the level we are assuming here. We will have to statethe
results of the experiment and point to the constancy of the velocity of light in all inertial
frames.
Thus, he continues :
If lighthas the same velocity relative to all inertialframes it can be shown by a rather simple
thought experiment that the duration of an event observed by different observers does not
have an absolute meaning.
Sears and Brehme (1968) take an even curter view of the historical background.
They introduce their account with the words:
The speed of light in a vacuum is 2.9979 x lo8 m s-’, or very nearly 3 x 10’ m s-’. Al
experimental evidence leads to the conclusion that this speed is the same for all observers,
regardless of theirmotions relativeto each other or to <strong>source</strong>s of light. This fact is the basis
of the theory of relativity.
The remainder of their account is concerned with the impact of this fact on a
wide range of physical theory. In their preface to the book, they say:
This is a text in <strong>physics</strong>. No attempt is made to discuss the philosophical or metaphysical
aspects of relativity. Nor is this text an account of the history of relativity. The famous
Michelson-Morley experiment, the first to suggest the invariance of the speed of light, is
barely mentionedand the ether appears only in a footnote. These interesting and historically
important aspects are not essential to an understanding of the theory.
Both of the lasttwo accounts stress the lack of necessity for an historical background.
H. Bondi (1965) goes even further and stresses its irrelevance. He calls
himself a ‘traditionist’ seeing the theory as a natural growth from classical
<strong>physics</strong>. He introduces his account as follows.
When the theory of relativity first came out, and for many years afterward, it was looked on
as something revolutionary. Attention was focused on the most extraordinary aspects of the
theory. With the passage of time, though, the sensational aspects of Albert Einstein’s work
have ceased to cause wonderment, at least among scientists, and now one begins to see the
theory not as a revolution, but as a natural consequence and outgrowth of all the work that
has been going on in <strong>physics</strong> since the days of Isaac Newton and Galileo.
This introduction sets the scene for the rest of the account. In developing the
special theory, he tries to show how unextraordinary the theory is, but how wrong
our original (pre-relativity) concept of time was, due to our limited experience of
high relative speeds.
402 Comparative Studies

The uniqueness of light is highlighted by dealing briefly with the ‘ absurdity of
the ether concept ’. A critical account of the Michelson-Morley experiment concludes
with the thought-provoking observation: ‘There can be no greater merit in
a scientific discovery than that before long it should appear very odd that it ever
was considered a discovery.’
A brief, but important survey of ‘ route-dependent ’ quantities like the distance
of a journey, introduces the idea that time is a ‘route-dependent’ quantity as well.
Before concluding this account of the various ways that have evolved of establishing
the Einstein principle of relativity. we must take note of one other quite
different approach to the whole theory. This we might call ‘dynamics first’.
There are today many experimental observations which can be made on bodies
travelling at speeds approaching that of light. This material was not available to
Einstein. But there is no reason why such experimental material should not be
used to teach the special theory. By using data from the acceleration of electrons
in a linear accelerator, A. P. French (1968) is enabled to introduce the study by
considering why the speeds of the electrons depart so widely from those predicted
by Newtonian dynamics. The data is obtained from a filmed experiment* made
for the P S S C ’ s Advanced Topics treatment of relativity only they used it to help
develop the dynamical consequences of relativity in its traditional place after
kinematic considerations.
A relationship between photon energy and momentum is shown to be similar
to that for high-speed electrons and French goes on:
This serves to reinforce our belief that the dynamics of photons and of other particles can be
brought, for some purposes at least, within the same descriptive framework. Our next step
will be to suggest what that framework might be. Our argument wlll appeal to one’s sense of
what is plausible; it will not be logically inescapable.
A thought experiment, originated by Einstein, shows that photons of energy E
have an effective mass E/?. The assumption is made that this link between energy
and mass may be universal. As a consequence formulae relating masses and kinetic
energies with speed are evolved and the latter is shown to fit the experimental data
from the film.
In this way the one ‘familiar’ result that most people associate with the Einstein
theory, namely E = mcz, is derived right at the outset, giving an incentive for a
deeper inquiry into the special nature of the speed of light.
C.3.3 The consequences of the principle of relutivity for our ideus of muss, length und time
One of the major difficulties which have always faced students in gaining an insight
into these consequences has been the lack of any real observational material
concerning the description of events taking place at speeds approaching that of
light. It is noteworthy that a body must have a speed of about one-seventh that of
light relative to an observer before a 1 per cent increase in its mass could be detected.
This scarcity of observational evidence has hitherto been supplemented by
* The Lilfimnfe Speed. a film produced by the Education Development Centre, Newton, Massachusetts.
403 The Special Theory of Relativity

An
‘thought experiments’. Einstein was probably the originator of these in his
‘popular’ account of relativity theory in 1916. Of late such thought experiments
have been extensively used in developing quantitative results, but as Bondi (1965)
points out these have taken on a new realism. Much of the quantitative development
in Relativity and Common Sense concerns the caperings of astronauts Alfred,
Brian and Charles, and he says :
When Einstein in 1916 wrotea book on relativity for the general public, he could think of no
better example to illustratehis ideas than to imagine indefinitely long trains running past
indefinitely long embankments at speeds approaching the velocity of light! . . . Far fetched
as they were, those trains afforded about the only possible images that would fallwithin the
layman’s understanding and not be dismissed as Jules Verne absurdities . . . .
Today, al this has changed. We send rockets to the moon and the vicinity of Venus. The
most stubborn sceptic no longer doubts that space stations of some sort will exist within the
lifetime of the youngest readers of these pages. Russian and American astronauts circlethe
Earth at speeds approaching 20000 miles an hour, and while our Brian’s 71 700 miles per
second is a far stretch from that figure, yet we can think quite realistically of speeds beyond
the ken of our fathers and grandfathers. Every day experimenters at the great accelerating
machines (the ‘atom smashers’) work with speeds nine-tenths of the velocity of light; relativisticeffects
are the regular order of their business. In a very few years special relativity has
come down from the clouds of phantasy or philosophic speculation to its rightful foothold
on the solid ground of the public domain.
It is in the nature of the human mind that learning is easier when a demonstrable need to
learn exists.Our fathers had no actual need to understand relativity, but we have, and we can
address ourselves to the adventures of Alfred, Brian and Charles without the emotional misgivings
that, forty years ago, upset passengers on Einstein’s indefinitely long trains. Alfred,
Brian and Charles are no less fictional but their manoeuvrings in space are representative
of situations which, in more complex details and refined form, command the attention and
challenge the laboratory skillsof today’s scientists and engineers.
The work of ‘ today’s scientists and engineers’ has also been put to good effect.
We have already seen how French has used a filmed experiment on high-speed
electrons to introduce his account. The PS SC which originally introduced this
film use another on the half-life of muons* to give reality to their work on time
dilation. French takes over this film in his own account as well.
Certainly these real and imagined experiments are an essential prop to understanding,
but the mathematics of the Lorentz transformations are unavoidable in
accounts which seek to be, in the words of Sears and Brehme, ‘a text in <strong>physics</strong>’.
The traditional sequence has already been outlined. An account of the relativity
of simultaneity precedes the Lorentz transformations. These in turn are applied
first of all to kinematic problems (length contraction, time dilation, composition
of velocities) and then to dynamic problems. Many recent authors have departed
from this order. The PSSC develops the law of composition of velocities first of
all; Bondi deduces the time-dilation formula at the outset; Sears and Brehme
* Time Dilution ~ Experiment with Mu-Mesons, a film produced by the Education Development
Centre, Newton, Massachusetts.
404 Comparative Studies

egin their account with the Lorentz transforms. French, as we have already seen,
begins with E = mc2.
In developing the essential mathematics, approaches have been numerous and
overlapping, but at the risk of over-simplification three trends can be
distinguished :
(a) Simplification of the traditional algebraic approach.
(b) The k-calculus.
(c) Geometrical approaches.
We wil look briefly at each of these.
Simplijkation of the traditional algebraic treatment. An example of this is the
PSSC’s treatment (PSSC. 1966). To give reality to the new formulae they
describe Fizeau’s experiment on the passage of light through moving water. The
shift in interference pattern is not used (as he used it) to measure the Fresnel drag
coefficient, but to show the need for a new law of combination of velocities. Their
derived result
21 + v
w=- 1 + ULl/CZ
is shown to fit the experimental results and they say:
Velocity, by definition, is displacement divided by time. If large velocities do not behave the
way we know low velocitiesto behave, then we become suspicious that our notions about
length and time may not be adequate. We shall have to examine carefully what we really
mean when we measure intervals of length and time in a frame of reference which is moving
with respect to us.
The need to synchronize two clocks for these measurements soon leads to the
realization that clocks synchronized for one observer wil not be synchronized for
another moving in respect to the first. By assuming that the relative velocity of two
observers (frames of reference) is much less than c, some simple (first-order)
transformations are worked out and the relativistic law for velocity combination
is shown to follow.
The Lorentz transformations are developed by introducing a necessary secondorder
correction of J( 1 - oz/c2) to make the transformations of distance and
time between the two frames symmetrical. The more detailed treatment of length
contraction and time-dilation which follows is enhanced by the filmed experiment
on the half-life of muons.
Eric Rogers in the section on ‘Relativity and Mathematics’ in Physicsfor the
Inquiring Mind deal9 with the difficulties of the mathematics in a different way.
Acknowledging its complexity, he says:
To understand relativity you should either follow its algebra through in standard texts, or,
as here, examine the origins and final results, taking the mathematical machine work on
trust.
405 The Special Theory of Relativity

To prepare for this approach, four pages of the chapter have previously been
devoted to obtaining a proper perspective of the place of mathematics in <strong>physics</strong>.
Here mathematics is shown to be a ‘language’ and a ‘clever servant’. After a
detailed discussion of tho attempts to measure the earth’s speed relative to the
‘ether’ the mathematical analysis needed to resolve the contradiction resulting
from these is assumed to be incorporated in a logic machine. This is the + clever
servant’ which can work out the answers to given questions when told all the
information you have and assumptions you wish to make.
The k-calculus. This approach to the mathematics of relativity was developed by
H. Bondi in Relativity and Common Sense and has been used in its essentials in
Senior Science for High School Students. W e wil outline Bondi’s own approach
here.
He tackles the mathematical development of the theory of relativity by an immediate
consideration of the way different inertial observers wil measure time
intervals. This is achieved by comparing the rate at which a succession of light
signals sent out by one observer with the rate they are received by another in
relative motion with respect to the first. In order to discuss the matter in concrete
terms an earth-bound observer, Alfred is imagined to be sending a regular succession
of light signals to a space station manned by David at rest relative to
Alfred. A third observer, Brian is travelling from Alfred to David and intercepts
these signals, sending out one of his own immediately he receives one of Alfred‘s.
Bondi concludes :
. . . if Alfred flashed his light at intervals h, then David would have seen these flashes at
intervals h, each flash taking the same time to reach him. Brian would have seen them at
some interval kh by his watch so that k is the ratio of the interval of reception to the interval
of transmission. If Brian flashes his torch at intervals kh by his watch, then these flashes,
travelling in company with those emitted by Alfred, would be seen at intervals h, giving the
reciprocal ratio Ilk between Brian and David.
After noting that the relationship between two inertial observers is completely
specified by the value of k, he says :
Note that the principle of relativity, by insisting on the equivalence of all inertialobservers,
makes it quite clear that the ratiok must be the same whichever of a pair of inertialobservers
does the transmitting. It is through this rule that our work on lightdiffers so sharply from
the work in sound where, it wil be remembered, the speed of transmitter and receiver
relative to the air had also to be taken into account.
Once this is established it can be shown that different inertial observers wil disagree
about the length of apparently corresponding time intervals. The extent of
their disagreement is of course the essential part of relativity theory. Bondi goes
on to show how k is related to the relative speeds of the two observers, and the law
of velocity composition and the Lorentz transformations are then evolved in
terms of k.
Geometrical approaches: Minkowski diagrams. In 1908 J. Minkowski described a
geometrical interpretation of the Lorentz transformations. In this an event is
406 Comparative Studies

described by four coordinates x, y, z and tin any one frame of reference. The complete
kinematic history of any point is represented by a line in four-dimensional
space withaxesx, y, z and t. This line is called a ‘world line ’.Since relativity theory
is usually concerned with two frames of reference in uniform motion with respect
to each other, the direction of this motion is made the x-axis and problems connected
with the description of a succession of events is limited to a consideration
of the two dimensions x and t.
Only recently have elementary accounts of Relativity theory made use of these
diagrams. Rekveld (1965) and French (1968) use them extensively. Rekveld says
The kinematical resultsof the theory on relativity . . . can also be derived by a geometrical
approach, in which the so-called Minkowski diagrams are used as visual aids. A geometrical
presentation of the theory may be applied either as an independent method or as a way of
supporting the algebraic discussion. In some cases the geometrical approach has advantages,
especially for the teachmg of concepts which ask a great deal of the imaginative
ability of the students.
He prepares the ground for their use later in developing the Lorentz transformations
by considering a geometrical representation of the Galilean transformation
(Figure 23a below). An event, E, is described by coordinates (xl, tl) in frame
(x, t) and by (xi, t;) in frame (x’, t’).
(a)
Figure 23
E, an event
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
rn
He later shows, as French does, that in order to describe correctly the passage
of a light signal in the two frames the x-axes should not be coincident (Figure 23b).
Once Figure 23b has been accepted it becomes an exercise in geometry to deal
with the Lorentz transformations, and length contraction and time dilation effects
canbevisualizedasdirectoutcomesfromchangesin(AE’),..n,t,,t and(AE),. constan,.
The use of Brehme diagrams. The Minkowski diagrams are not the only way to
make a geometrical approach to relativity theory. To illustrate this we wil consider
one other geometrical approach from the many which are possible. This is
407 The Special Theory of Relativity
I
I
I
XI
*
X

the approach devised by R. W. Brehme and used extensively in Introduction to
the Theory of Relativity (Sears and Brehme, 1968).
Sears and Brehme also introduce their geometrical representation by considering
first the Galilean transformation. An event Eis represented by coordinates
(xl, tl) in frame (x, t) and by (xi, ti) in frame (x’, t’), below (Figure 24a). As they
state in their book: ‘The coordinates of events are found by dropping perpendiculars
to the axes, even though the axes are not orthogonal.’
(a)
Figure 24
In this case it is the t-,t’-axes which are coincident. One special difficulty in
using the Minkowski diagrams is that the scales on thex- and XI- and on the t- and
t’-axes are not identical, i.e. unit time interval is not the same graph length on
both t and t’. As a result lengths may look longer in (x, t) than in (x’, t’) but may
in fact be shorter. In the Brehme diagrams the graph scales are identical.
In order to describe correctly the passage of a light signal in the two frames of
reference, it can be shown that the t- and t’-axes cannot be coincident (Figure
24b). The angle 4 between the t- and t’-axes is only the same as the angle between
the x- and the x’-axes if there is a scale factor c (the speed of light) between x- and
t- (and thus XI- and t’-) axes.
Again, once these diagrams have been understood, the consequences of the
principle of relativity are very easy to visualize and calculate. Another feature of
these particular diagrams is that owing to their symmetry neither (x, t) nor (x’, t’)
frame of reference seems specially preferred.
408 Comparative Studies

C.3.4 Conclusion
The aim of this section has been to show how numerous and various have been the
recent approaches to elementary or introductory treatments of the theory of
relativity. It must be emphasized again that the examples used have only been
chosen in order to illustrate this variety. It will,it is hoped, have been seen that no
one approach is unique, and yet all have unique features. It is thus clear that if
twenty different approaches were described, a twenty-first could be devised by
using particularly favoured features from each one.
409 The Special Theory of Relativity

References
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International Conference on Physics Education, Unesco, Paris.
ARISBR (1968), The Design of Physics Laboratories for Asian Second Level Schools,
Asian Regional Institute for School Building Research: Study no. 4.
BLOOM, B. S. (1965), Taxonomy of Educational Objectives, Longmans.
BONDI, H. (1965), Relativity and Common Sense, Heinemann.
BOUTRY, G. A. (1964), ‘The historical approach in the teaching of <strong>physics</strong>’, in Why
Teach Physics, The MI T Press.
BRIMER, A., et al. (1969), The Bristol Achievement Tests. Interpretative Manual, Nelson.
BRITISH COMPUTER SOCIETY (1970), Cornputer Education for All.
BROWN, S. C., CLARKE, N., and TIOMNO, J. (1964), Why Teach Physics, The MIT
Press.
BRUSH, S. G. (1969), ‘The role of history in the teaching of <strong>physics</strong>’, The Physics
Teacher, vol. 7, no. 5, pp. 271-80.
CIES (1968), Report on the Congress on the Integration of Science <strong>Teaching</strong>, Droujba,
Bulgaria, CI E S.
CLEGG, J. A. (1969), ‘Physics centres’, Physics Bulletin of the Institute of Physics and the
Physical Society, London, vol. 20, October, p. 412.
CODLING, J. C. (1966), ‘Computer circuits’, School Science Review, vol. 48, no. 164,
p. 201.
COMMISSION ON COLLEGE PHYSICS (1968), Preparing High School Physics Teachers,
Department of Physics, University of Maryland.
C o M MON w EA L TH ED U c A T I o N L I A I s o N COMMITTEE (1 964), School Science
<strong>Teaching</strong>, Report on an expert conference held at the University of Ceylon, December
1963, HMSO, London.
CUMBERS, J. (1969 and 1970), ‘Analogue computing for <strong>school</strong>s’, Computer Education,
3,4 and 5,85, 21 and 6.
DALZIEL, A. (1967),‘FABCAT: Fast acting binary counter and timer’, School Science
Review, vol. 48, no. 165, p. 394.
DURLING, J. R. (1970), ‘MAC- an educational analogue computer’, Physics Education,
vol. 5, p. 206.
DUTTON, P. E. (1966), ‘Introducing SUSAN’, School Science Review, vol. 47, no. 162,
p. 426.
DUTTON, P. E. (1968a), ‘Progress report on SUSAN’, School Science Review, vol. 49,
no. 162, p. 906.
410 References

DUTTON, P. E. (1968b), ‘The place of computing in <strong>school</strong>s’ <strong>physics</strong> courses’, Physics
Education, vol. 5, p. 206.
EARTH SCIENCE CURRICULUM PROJECT (1967), Investigating the Earth, Houghton
Mifflin.
EINSTEIN, A. (1923), ‘On the electrodynamics of moving bodies’, from Principle of
Relativity, translated by W. Perrett and G. B. Jeffery, Dover.
FAFUNWA, A. B. (1967), New Perspectioe in African Education. Macmillan.
FEYNMAN, R. P., LEIGHTON, R. B., and SANDS, M. (1964), The Feynman Lectures on
Physics (3 vols.), Addison-Wesley.
FLETCHER, T. J. (1964). Some Lessons in Mathematics, Cambridge University Press.
FRENCH, A. P. (1968), Special Relativity, Nelson.
GAY, J. H., and COLE, M. (1967). The New Mathematics and an Old Culture, Holt,
Rinehart & Winston.
GEORGE, F. (1969). ‘Government by computer’, Science Journal, September, p. 76.
HARVARD PROJECT PHYSICS (1969), ‘Teachers Guide, An Introduction to Physics 3’,
The Triumph of Mechanics, Holt, Rinehart & Winston.
HINSON. D. J. (1968 and 1969), ‘A transistor analogue computer’, School Science
Review, vol 49, no. 170, p. 138, and vol. 50. no. 173, p. 888.
HMSO (1960), Science in Secondary Schools, Ministry of Education Pamphlet no. 38,
Her Majesty’s Stationery Office, London.
HOLTON, G. (1963),‘Physics and culture’. Bulletin of the Institute of Physics and the
Physics Society, December, pp. 321-9.
INDIAN EDUCATION COMMISSION (1966), Reports of the Education Commission
19644, Ministry of Education, Government of India.
JAMES, K. (1969).‘Human perception and machine intelligence’, Schools Council
Project Technology Bulletin II, p. 178.
JONES, G. 0. (1969), ‘Physics in the new London B. Sc. degree’, Phvsics Education.
vol. 4, May, p. 143.
JOSHI, A. C. (1963), Science and Technology for Development, United Nations.
KELLY, D. T. (ed.) (1969),‘School science and technology’, Schools Council Project
Technology, no. 184.
KOTHARI, D. S. (1964), The Problems of Scientific and Technical Terminology in Indian
Languages, Government of India.
LEITH, G. 0. M. (1968),‘Age, personality and learning aptitudes’. Impact on Science on
Society. vol. 8, no. 3, pp. 174-7, Unesco.
MACKMAN, E. W. (1967),‘A <strong>school</strong> analogue computer’, School Science Reuiewx, vol.
49, no. 167. p. 113.
MAGIE, W. F. (1935), Source Book in Physics, Harvard University Press.
MEAD, M. (1959), ‘Closing the gap between scientists and others’, Daedalus, vol. 88,
pp. 139-146.
MENDOZA. E. (1962),‘The historical approach to the mechanical theory of heat’.
School Science Review. vol. 44, no. 152, p. 11.
MILLBOURN, M. (1960), ‘Graduate physicists in industry’, in N. Clarke (ed.) A Physics
Anthology, Chapman & Hall, p. 246.
41 1 References

MPEMBA, E. B., and OSBORNE, D. G. (1969), ‘Cool?’, Physics Education, May, p. 172.
NATIONAL COMMISSION OF COLLEGE PHYSICS (1962), ‘Progress report of the
Commission on College Physics’, American Journal of Physics, vol. 30, October, p. 17.
NEDELSKY, L. (1956), Science <strong>Teaching</strong> and Testing, Harcourt, Brace & World.
NEWMAN, J. R. (ed.)(1956), The World of Mathematics, vol. 2, Simon & Schuster.
NUFFIELD PHYSICS (1966), Nufield Physics Teachers’ Guides, Volumes 1-5, Longman/
Penguin.
O’DOWN, D. D., and BEARDSLEE, D. C. (1961),‘The college student image of the
scientist’, Science, vol. 133, pp. 997-1001.
OECD (1965), <strong>Teaching</strong> Physics Today, OECD Publications, Paris.
OGBORN, J. M. (1961), ‘A simple digital computer using relays’, School Science Review,
vol. 43, no. 149, p. 58.
OREAR, J. (1967), Fundamental Physics, 2nd edn, Wiley.
PARSE GIAN, V. L. (1969), ‘Giving relevance to science’, The Physics Teacher, October,
pp. 379-84.
PARSEGIAN, V. L., MELTZER, A. S., LUCHINS, A. S., and SCOTT KINERSON, K.
(1968), The Physical Sciences, Academic Press.
PARSEGIAN, V. L., MONAGHAN, E. V., SHILLING, P. R., and LUCHINS, A. S.
(1968), The Life Sciences, Academic Press.
PIAGET, J., and INHELDER, B. (1958), The Growth of Logical Thinking, Routledge &
Kegan Paul.
PIDGEON, D., and Y ATES, A. (1969), ,An Introduction to Educational Measurement,
Routledge & Kegan Paul.
PSSC (1960), Teachers’ Re<strong>source</strong> Book and Guide, Part ZZZ, Heath.
P S S C (1966), Advanced Topics Supplement, Heath.
REKVELD, J. (1965),‘Relativity’,
Chapter 10 of <strong>Teaching</strong> Physics Today, OECD.
ROGERS, E. M. (1960), Physics for the Inquiring Mind, Princeton University Press.
S ARTON, G. (1952), A History of Science, Harvard University Press.
SCOTTISH EDUCATION DEPARTMENT (1969), Computers and the Schools - An
Interim Report.
SEARS, F. W., and BREHME, R. W. (1968), Introduction to the Theory of Relativity,
Addison- Wesley.
SILLARS, R. W. (1960),‘Physics and engineering’, in N. Clarke (ed.) A Physics Anthology,
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41 2 References

Further Reading
Books
C. S. ADAMS, Measurement andEiraluation in Education, Holt, Rinehart & Winston, 1964.
ASIAN REGIONAL INSTITUTE FOR SCHOOL BUILDING RESEARCH, The Design of
Physics Laboratories for Asian Second-Leiiel Schools, Unesco, 1968.
ASSOCIATION FOR SCIENCE EDUCATION et al.. <strong>Teaching</strong> ofscience in Secondary
Schools, Murray. 1970.
B. S. BLOOM et al., Taxonomy ofEducationa1 ObjectiLles ~ Handbook I, Cognitiiie Domain,
Longman, 1956.
P. F. BRANDWEIN, F. WATSON and P. BLACKWOOD, <strong>Teaching</strong> High School Science,
Harcourt, Brace & World, 1958.
A book of methods.
J. BRIERLEY (ed.), Science in its Context, Heinemann, 1964.
BRITISH COMPUTER SOCIETY, Computer Education for All, British Computer Society,
1970.
S. C. BROWN and N. CLARKE (eds.),InternationalEducation in Physics, Wiley, 1960.
The proceedings of the International Conference on Physics Education, Unesco. Paris,
1960.
S. C. BROWN and N. CLARKE (eds.), The Education of a Physicist, Oliver & Boyd, 1966.
An account of the IUPAP international conference on the education of professional
physicists, London, July 1965.
S. C. BROWN, N. CLARKE and J. TIOMNO (eds.), Why Teach Plz.vsics? The MIT Press,
1966.
Based on the discussions at the International Conference on Physics in General
Education, Rio de Janeiro, July 1963.
S. C. BROWN, F. KEDvEsandE. J. WENHAM(eds.). <strong>Teaching</strong>Physics~AnInsoluble Task?
The MIT Press, 1971. Proceedings of the Egar Conference, 1970.
J. S. BRUNER, The Process of Education, Harvard University Press, 1960.
Perhaps the best briefintroduction to the application of current thought about the
learning process to the teaching of the sciences.
N. CLARKE (ed.), A Physics Anthology, Chapman & Hall, 1960.
A collection of papers on topics of interest to <strong>physics</strong> teachers.
COMMISSION ON COLLEGE PHysrcs, Preparing High School Physics Teachers,
University of Maryland, 1965.
A report of the panel on the preparation of <strong>physics</strong> teachers.
COMMON WEALTH EDUCATION LIAISON CO MM IT TEE, School Science <strong>Teaching</strong>,
Her Majesty’s Stationery Office, London.
A report of an expert conference at University of Ceylon, December 1963.
413 Books

Z. P. DIENES, Concept Formation and Personality, Leicester University Press, 1959.
Includes a description of mathematical concept formation.
J. F. EGGLESTON and J. F. KERR (eds.), Studies in Assessment, English University Press,
1969.
A. B. FAFUNWA, New Perspective in African Education, Macmillan, 1967.
R. P. FEYNMAN et al., The Feynman Lectures on Physics, Addison-Wesley, 1964.
J. M. FOWLER, P. G. ROLL and B. Z. BLUESTONE, The Computer in Physics Instruction,
Commission on College Physics, 1966.
Report on the conference on the uses of the computer in Physics Instruction in the
University of California, November 1965.
E. J. FURST, Constructing Evaluation Instruments, McKay, 1958.
M. L. GAGE (ed.), Handbook of Research on <strong>Teaching</strong>, Rand McNally, 1964.
J. H. GAY and M. COLE, The New Mathematics andan Old Culture,
Holt, Rinehart & Winston, 1958.
P. GILLON and H. GILLON (eds.), Science andEducation in Developing States, Praeger,
1971.
The proceedings of the Fifth Rehovot Conference in Israel.
B. HOFFMANN, The Tyranny of Testing, Cromwell-Collier, 1962.
An attack on the claims of objective testing.
G. HOLTON, Introduction to Concepts and Theories in Physical Science, Addison-Wesley,
1952.
G. HOLTON and D. H. D. ROLLER, Foundations of Modern PhysicalScience,
Addison-Wesley, 1965.
J. G. HOUSTON, Principles of Objective Testing in Physics, Heinemann, 1970.
B. INHELDER and J. PIAGET, The Growth ofLogica1 Thinking, Routledge & Kegan Paul,
1958.
INSTITUTE OF PHYSICS AND ROYAL SOCIETY, Teacher Training for Physics
Graduates, Institute of Physics and Royal Society, 1969.
A report of a joint committee.
IUPAP, A Survey of the <strong>Teaching</strong> of Physics at Universities, Unesco, 1966.
D. R. KRATHWOHN et al., Taxonomy of Educational Objectives- Handbook II, Afective
Domain, McKay, 1964.
E. F. LINDQUIST (ed.), Educational Measurement, American Council on Education,
1955.
K. LOVELL, The Growth of Basic Mathematical and ScientiJc Concepts in Children,
University of London Press, 1961.
Introductory account of the work of the Piagetian <strong>school</strong>.
MINISTRY OF EDUCATION PAMPHLET NO. 38, Science in Secondary Schools,
Her Majesty’s Stationery Office, London, 1960.
L. NEDELSKY, Science <strong>Teaching</strong> and Testing, Harcourt, Brace & World, 1965.
J. R. NEWMANN, The World of Mathematics, Simon & Schuster, 1956.
N E w ZEALAND Po s T-P R I M A R Y TEA c HE R s As s o c I A T IO N, Education and Change,
Auckland: Longman Paul, 1969.
G. R. NOAKES (ed.), Sources of Physics <strong>Teaching</strong>, Parts 1-5, Taylor & Francis, 1968-70.
Reprints of papers on <strong>physics</strong> teaching from Contemporary Physics; many of these were
originally commissioned by the Nuffield Science <strong>Teaching</strong>.Project.
NUFFIELD SCIENCETEACHING PROJECT, Guide to Apparatus, Penguin Books,
Longman, 1966.
414 Further Reading

OECD, <strong>Teaching</strong> Physics Today, OECD publications, 1965.
A collection of papers to inform teachers on current development and modern views in
the teaching of <strong>physics</strong> at the secondary level.
D. PIDGEON and A. YATES, An Introduction to Educational Measurement,
Routledge t Kegan Paul, 1969.
E. M. ROGERS, Physics for the Inquiring Mind, Princeton University Press, 1960.
SCOTTISH EDUCATION DEPARTMENT CURRICULUM PAPER NO. 7, Science for
General Education, Her Majesty's Stationery Office, Edinburgh.
S. SIKJAER (ed.), The <strong>Teaching</strong> ofPhysics in Schools, Gyldendal, 1971.
Collections of papers from a seminar organized by GI REP at the Royal Danish
School of Educational Studies, Copenhagen, July/August 1969.
R. A. R. TRICKER, Contribution of Science to Education, Mills & Boon, 1967.
<strong>UNESCO</strong>, New Trends in Physics <strong>Teaching</strong>- Volume I, Unesco, 1968.
A collection of papers concentrating on innovations introduced into <strong>physics</strong> teaching
between 1960 and the date of publication.
<strong>UNESCO</strong>, New Trends in Physics <strong>Teaching</strong> - Volume II, Unesco, 1972.
A further collection of papers concerned with new methods of teaching <strong>physics</strong>.
J. G. WALLACE, Concept Growth and the Education of the Child, National Foundation
for Educational Research, 1965.
An extensive survey of recent work on conceptualization.
J. W. WARREN, The <strong>Teaching</strong> oj'Physics, Butterworth, 1965.
An expost of certain erroneous ideas which are common in <strong>physics</strong> teaching.
V. F. Yus 'KO VICH (ed.), Methadr of <strong>Teaching</strong> Physics in Soriet Secondary Schools,
Proceedings of the Institute of <strong>Teaching</strong> Methods, Academy of Pedagogic Sciences.
RSFR; English translation, Oldbourne Press, 1966.
Series
Longman Physics Topics, edited by J. L. Lewis, Longman, 1969.
A series of background <strong>books</strong> for pupils aged 11-18, designed for use with modern
Physics courses.
Study Series, Heinemann, 1964.
A series of <strong>books</strong> for further reading by students, written originally for P S S C.
Projects
Earth Science Curriculum Project, Houghton Mifflin, 1967.
Fkica de la Luz (2nd revised edition), Madrid: ENOSA, 1968.
Eysik (Scandinavian version of PSSC), Stockholm: Biblioteksforlaget, 1968.
Introduction to Natural Science, Academic Press, 1970.
Introductory Physical Science, Prentice-Hall, 1967.
The Man-Made World (ECCP). McGraw-Hill, 1971.
Nufield Adoanced Physics, Penguin Books, 1972.
Nufield Combined Science, Penguin Books; Longman, 1970.
Nufield Physical Science, Penguin Books, 1972.
Nufield Physics. Penguin Books ; Longman, 1966.
Nufield Secondary Science, Longman, 197 1.
Physical Science for Nonscience Students. Wiley, 1969.
Project Physics Course, Holt, Rinehart & Winston, 1970.
415 Projects

PSSC Advanced Topics Supplement, Heath, 1966.
PSSC Physics, Heath, 1960.
Science for High School Students, New South Wales : Government Printer, 1968.
Senior Science for High School Students, New South Wales: Government Printer, 1968.
Journals
Contemporary Physics, A journal of interpretation and review (1959), bi-monthly.
Taylor & Francis, Red Lion Court, Fleet St, London EC4.
Computer Education, A joint publication of the Computer Education Group and Schools
Council Project Technology (1969), 3/year. Schools Council Publications,
160, Great Portland St, London W1.
Education in Science, The Bulletin of the ASE (1963), 6/year. Association for Science
Education, College Lane, Hatfield, Herts.
Physics Education (1966), 6/year. The Institute of Physics and the Physical Society,
47, Belgrave Square, London SW 1.
Physics Teacher (1963), 8/year. American Association of Physics Teachers,
1201 Sixteenth St, NW, Washington 6, DC.
School Science Review (1919), 3/year. John Murray, 50, Albemarle St, London W1.
School Technology (fo~merly the Bulletin of the Schools Council Project Technology),
S/year. Schools Council Publications, 160, Great Portland St, London W 1.
416 Further Reading