The Pet Rock Project - NSTA Learning Center

SCIENCE SAMPLER
The Pet Rock Project:
Making the rock cycle
come alive!
!
The rock cycle is often considered to be one of the
main themes in Earth science because it summarizes
the internal and external processes responsible for the
formation and alteration of the Earth’s materials. In
diagram form, the rock cycle conveniently portrays the
pathways and subpathways by which the various rock
types—igneous, sedimentary, and metamorphic—can be
created. Although geology is considered to be a young
science, the rock-cycle diagram appeared early in its
history; in 1838, Charles Lyell published his Elements
of Geology with a stylized version of the rock cycle as the
hand-colored frontispiece.
The typical rock-cycle diagram visually represents
the complex series by which a rock type may be altered
to another rock type, or further altered to produce a new
variety of its current form. Many diagrams incorporate
more than one subpathway for a transformation,
and some diagrams include photographs. However,
the complexity of the rock cycle requires further
exploration of the various subpathways for students
to actually understand and remember the intricacies
of the processes represented. This project was our
response to students’ confusion about the rock cycle,
one of the fundamentally important concepts within the
geosciences.
Some published student activities address the
importance of minerals and their role in rock formation
(Paty 2000; Smith 2000), while others offer suggestions
for introducing the rock cycle in the classroom (Frack
and Blanchard 2005; Plummer and Kuhlman 2005).
We developed our activities to provide a more in-depth
learning experience by personalizing the rock cycle and
involving our students’ artistic and creative abilities in
the Earth science classroom. The idea of a pet rock was
central to the project as a mechanism to make Earth
science seem more inviting to reluctant learners. Our
focus on the development of a rock “animal” is supported
by science education research, which reveals that middle
school students report more interest in learning about
animals versus plants—partly because animals have
human-like faces and can interact with people, and their
life cycles are easily observed (Wandersee 1986).
Procedure
The Pet Rock Project can be used at various grade levels,
with appropriate modifications in content. This project
addresses several National Science Education Standards
(NRC 1996), including NS.5-8 Unifying Concepts
and Processes Standards (evidence, models, and
explanation) and Content Standard D in Earth and Space
Science (Earth’s history). We incorporated the Pet Rock
Project within our classroom after an introduction to the
rock types, so our students had some understanding of
the characteristics of sedimentary, metamorphic, and
igneous rocks, and the basic processes by which each
rock type could form. The Pet Rock Project was then
used to consolidate basic content knowledge and further
probe rocks and the rock cycle.
Materials
Pet Rock Project guidelines
• Rock samples (teacher provided or student gathered,
one per student) Note: Rock samples may be
obtained from several commercial establishments if
samples are not easily obtained from natural settings.
For example, department stores’ garden centers usually
carry “lava rocks” (igneous), marble chips (metamorphic),
and “river rocks” or “gravel” (often chert,
sedimentary) rocks. We personally have received
rock donations from concrete suppliers.
• Assorted art supplies (paper, colored pencils, crayons,
markers)
• Pet Rock Project rubric (Figure 2)
Directions
The teacher introduces the three types of rocks with an
illustrated diagram of the rock cycle. Several rock-cycle
diagrams are accessible online, including one on the
Rocks and Minerals website (www.rocksandminerals.
com/rockcycle.htm), and another on a USGS website
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SCIENCE SAMPLER
FIGURE 1
Pet Rock Project directions
1. Your assignment is to find a rock—igneous,
sedimentary, or metamorphic—that you wish to
“adopt.”
2. You may turn in your rock “as is,” or you may alter your
rock in a number of ways to personalize it. However,
at least part of the original rock’s surface must be
visible.
3. When you turn in your pet rock, please also turn in a
paper that answers the following questions:
• Where and when did you find this rock?
• Why did you choose this rock?
• What type of rock do you have? Why do you think it is
this type?
• Describe any tests or ways you might determine
exactly what type of rock you have.
• Have you altered your rock in any way? If so, describe.
Why have you done this?
• Draw your own version of the rock cycle.
• Locate your pet rock on the rock cycle.
• Describe how YOUR rock could possibly be transformed
into the other rock types on your rock-cycle diagram.
Your pet rock is due on ________ by the end of class.
(http://3dparks.wr.usgs.gov/nyc/common/geologicbasics.
htm). Students are asked, “Can one type of rock form
the other types of rocks?” and “Can a rock of a certain
type form a new rock of the same type?” The teacher
encourages students to describe the rocks they encounter
in their daily lives. We have used the “Geological Sense
of Place” writing template activity (Clary and Wandersee
2006) to probe students’ childhood memories and
experiences with rocks and Earth processes. Students
can also be grouped, and asked to explain the statement,
“Your house comes out of a mine.” Each group produces
a cooperative list of household materials that originate
as rocks or minerals.
Teachers may explore, as a historical-cultural
option, the concept of pet rocks that was developed
by Gary Dahl as a marketing gimmick in 1975. As
the perfect undemanding “pet,” these rocks became
a commercial success, and made Dahl a millionaire
(Polson Enterprises 2006). Students may be divided
into cooperative learning groups, and investigate the
historical, political, and cultural context into which the
pet rock marketing success evolved. Each group can
identify the favorable characteristics of “pet rocks,” the
probable “roles” these “pets” fulfilled in their owners’
lives, and hypothesize whether a similar marketing
gimmick would be successful today. Creativity in the
construction of pet rocks can be demonstrated through
various websites that have used decorated rocks as
fund-raisers (www.uwlax.edu/geography/html/Pet-Rock
Making.htm), and as hands-on activities within
English classes for speakers of other languages (www.
mrshurleysesl.com/petrocks.html). Introduction of these
rock projects to students when the project is first
assigned can illustrate the range of possibilities for the
Pet Rock Project, and also reassure reluctant learners
that creativity within the project is not difficult.
The original Pet Rock Project comprised a two-week
period of rock-finding, investigating, and reporting.
Figure 1 summarizes the original handout for the
project. We think that within a typical middle-level
class that meets daily, the Pet Rock Project should be
allotted a five-day period for location and development
of a rock sample, preferably with a weekend available
for students to initially collect their rock samples. The
rubric utilized in scoring the projects is also provided
to students (Figure 2).The teacher directs students
to locate a rock outside of the classroom, and identify
the rock as igneous, sedimentary, or metamorphic.
(Alternatively, the instructor may bring in a bucket of
known rocks, and allow students to choose a favorite
to use in this project. Teacher-supplied rocks would
shorten the required time for the activity; we feel a
minimum of three classroom days would be appropriate
in this situation. Whereas we personally like the idea of
students procuring their own rocks, we acknowledge
that in some schools this may present a problem for the
majority of students.)
Students may decorate or embellish their pet rocks,
as long as some of the original rock material is left
unaltered and exposed. Students then develop their
own version of the rock cycle, and locate their rock
within the rock cycle. Students have a variety of options
in which to create a rock cycle, including an electronic
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SCIENCE SAMPLER
FIGURE 2
Pet Rock Project rubric.*
Student name ___________________
CATEGORY 10 8 6 4
Required
elements
The project includes
all required elements
as well as additional
information.
All required
elements are
included in the
project.
All but one of the
required elements
are included in the
project.
Several required
elements are
missing.
Explanatory
paragraph:
Accuracy
At least four accurate
facts are displayed.
Three accurate facts
are displayed.
Two accurate facts
are displayed.
Less than two
accurate facts are
displayed.
Originality
Several of the
components reflect an
exceptional degree of
student creativity in
their construction or
display.
One or two
components used
reflect student
creativity in their
creation or display.
The components are
made by the student,
but are based on the
designs or ideas of
others.
No components
made by the student
are included.
Graphics
Attractiveness
All components are
related to the topic
and make it easier
to understand.
All borrowed
components have a
source citation.
The project is
exceptionally
attractive in terms of
design, layout, and
neatness.
All components
are related to the
topic and most
make it easier
to understand.
All borrowed
components have a
source citation.
The project is
attractive in terms of
design, layout, and
neatness.
All components
relate to the topic.
Most borrowed
components have a
source citation.
The project is
acceptably attractive
though it may be a
bit messy.
Components
do not relate
to the topic OR
several borrowed
components do
not have a source
citation.
The project is
distractingly messy
or very poorly
designed. It is not
attractive.
* This rubric may be modified according to the background and skills of the student population, and the extent of the investigation
of the rock cycle in the classroom.
version, a collage, a poster, or a plain-paper version.
Students may use website images, their textbooks, or
photographs from magazines or journals. All outside
materials, whether from the internet or paper journal,
should be cited by students. (We assume that the
teacher has provided basic directions to students on
how to conduct internet searches, including information
on image searches and reliability of websites, before
students are encouraged to use the internet.) Although
these activities were originally assigned as out-of-class
assignments, they can easily be incorporated into the
traditional classroom. In addition to producing their pet
rock, students develop a written report justifying the
identification of their rock, and describing how their pet
may be turned into the other types of rocks. Creativity
is encouraged.
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SCIENCE SAMPLER
FIGURE 3
One student participating in the Pet Rock Project chose a common piece of Mississippianage
chert as her adopted rock. Modifications include the addition of cardboard legs, tail, and
head to create a camel.
A. B.
photos courtesy of the authors
FIGURE 4
“Slick,” a piece of obsidian, was
personalized with the addition
of formal attire
Discussion and findings
We were pleasantly surprised and impressed by the variety
of Pet Rock Projects that we received. Most of the rocks
students submitted were samples of chert gravel, used
locally to build roads. However, many students creatively
embellished their rocks, or added props or features
(Figure 3), and some of the pet rocks submitted were
collected by students outside of the state (Figure 4).
One of our favorite submissions was scoria, a
volcanic rock often used for landscaping. The student
named her rock “Dat” (Figure 5) in honor of the New
Orleans Saints, and creatively relayed the story of how
this “football rock” could be transformed into other
rock types (Figure 6). Although the student incorrectly
identified her rock as pumice, the stor y reveals
incredible creativity as well as an understanding of
the internal and external processes that operate on
the surface of and within Earth.
Student-created rock cycles also exhibited
understanding of the interrelatedness of igneous,
sedimentary, and metamorphic rocks. Some students
produced their rock-cycle diagrams by drawing, some
students created rock-cycle diagrams electronically, and
some students fashioned rock-cycle diagrams with shape
cut-outs. Three examples of student rock cycle diagrams
are presented in Figure 7.
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SCIENCE SAMPLER
FIGURE 5
“Dat,” a piece of scoria, was
altered only by the addition of
his “team symbol.” The rock’s
story and relationship within
the rock cycle are presented in
Figure 6.
FIGURE 6
Student submission of pet rock
relationships. This story exhibits
a higher level of creativity than
typical student submissions.
Conclusion
Students may often encounter so many facts, concepts,
and theories in a science class that they exit the class at
the end of the year with only a skeletal understanding of
isolated scientific principles. Some constructs in Earth
science, such as plate tectonics and the rock cycle,
are unifying themes in the geosciences and deserve
more than a cursory glance by students. Thorough
understanding of these important constructs provides
a knowledge base within Earth science on which
further topics can be linked and scaffolded. We think,
based on students’ submitted projects and anonymous
student survey data, that the Pet Rock Project was
successful in promoting a more in-depth understanding
of the rock cycle. Because the project involves the
“adoption” of a rock, we think that the Pet Rock Project
may possibly promote personal meaning-making in the
classroom by targeting students’ affective as well as
their intellectual domains, and giving students multiple
relevant opportunities to retrace and internalize rock
cycles’ subpathways. Furthermore, varying degrees of
content knowledge may be easily incorporated within
the assignment so that it can be implemented at various
grade levels. We encourage other science teachers to
creatively explore the investigation of rock properties
and the rock cycle through the Pet Rock Project.
References
Bybee, R.W., and A.H. Pratt. 1996. National standards: Challenges
for Earth science education. Geotimes 41: 16–19.
Clary, R.M., and J.H. Wandersee. 2006. A writing template
for probing students’ geological sense of place. Science
Education Review 5 (2): 51–59.
Frack, S., and S.A. Blanchard. 2005. Rockin’ around the
rock cycle. Science Scope 29 (2): 62.
Lyell, C. 1838. Elements of geology. London: John Murray.
Mantell, G. 1836. Thoughts on a pebble, or a first lesson
in geology. London: Relfe and Fletcher.
Mintzes, J.J., J.H. Wandersee, and J.D. Novak, eds. 1998.
Teaching science for understanding: A human constructivist
view. San Diego, CA: Academic Press.
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FIGURE 7
Students produced their own renditions of the rock cycle, using a variety of media and
techniques. The rock cycle on the upper left accompanied “Dat,” the igneous rock,
while the lower left rock cycle is a computer-generated version.
National Research Council (NRC). 1996. National science
education standards. Washington, DC: National Academy
Press. Available online at www.nap.edu/readingroom/books/nses.
Paty, A.H. 2000. Rocks and minerals—Foundations of our
society. Science Scope 23 (8): 30–31.
Plummer, D., and W. Kuhlman. 2005. Rocks in our pockets.
Science Scope 29 (2): 60–61.
Polson Enterprises. 2006. The Pet Rock page. www.virtualpet.com/vp/farm/petrock/petrock.htm.
Sife, W. 1998. The loss of a pet. Hoboken, NJ: Howell Book
House—John Wiley and Sons.
Smith, S. 2000. Turning bread into rocks: A multisensory
unit opener. Science Scope 24 (2): 20–23.
Wandersee, J.H. 1986. Plants or animals: Which do junior
high school students prefer to study? Journal of Research
in Science Teaching 23: 415–26.
Renee Clary (rclary@geosci.msstate.edu) is an assistant
professor of geology in the Department of Geosciences
at Mississippi State University in Mississippi
State, Mississippi. James Wandersee is an endowed
professor of biology education in the Department of
Educational Theory, Policy, and Practice at Louisiana
State University in Baton Rouge, Louisiana.
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