Abstracts - Earli

case of time, as one of the fundamental categories of thought (Piaget 1969, Ogborn & Mariani1995), we carried out a researching program for three years in Athens. In the first phase of ourprogram, we recorded pupilsb conceptions of time, following the Piagetian method of clinicalinterview. At the second phase of our program we expanded our study to the social constructivistfield; and we tried to help pupils to scaffolding their ideas about time. We designed a researchprogram to study a curriculum including teaching strategies adapted to children of 9-10 years. Atthe third phase we created open learning environments (Roth, 1995), and we used learningstrategies, such as dialogues (Lemke, 1990), argumentation (Toulmin, 1958, Walton, 1996),academic controversies (Johnson & Johnson, 1995) etc. Pupils exchange their ideas, they weretelling stories about time, and they argued using many types of justifications. They challengedeach other; but also they negotiate their ideas and make a synthesis that made meaning to them.The first outcomes of this project show off the necessity of integration through inter-disciplinarity.Students’ reasoning approaches to multi-criteria decision-making situations in the context ofsocio-scientific issuesNicos Papadouris, Learning in Science Group, University of Cyprus, CyprusConstantinos Constantinou, Learning in Science Group, University of Cyprus, CyprusThis paper reports on an empirical study that is targeted at identifying and documenting thevarious reasoning difficulties encountered by students while processing information in the contextof decision-making situations that require multiple criteria. Data were collected through interviewswith 18 individual students (9 sixth-graders and 9 eighth-graders). We have used tasksconcentrating on the fictitious selection of the most appropriate site for a new power plant. Dataanalysis demonstrates some prevalent reasoning patters. One of these includes distorting theavailable evidence through eliminating certain aspects of information and selectively attending to alimited portion of the data. Another common approach involves directly comparing informationwithout adjusting for the variability relevant to the diverse metrics used to express raw data.Finally, a third approach involves making a decision on the basis of the rankings of the alternativesolutions across the various criteria. We demonstrate that these approaches are the outcome of anumber of prevalent reasoning difficulties. Two of these difficulties include students’ failure toappreciate the need to take into account the entirety of available data and their lack of awarenesswith respect to the confounding that stems from the variability in the metrics used to express rawdata. The information provided by this study enlightens school students´ attempts to makedecisions in complex situations and highlights some of the reasoning strategies that arespontaneously activated by the students. The findings could be used to inform any attempt todevise learning materials for developing students’ reasoning skills in dealing with multi-criteria,decision-making situations.– 326 –