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Asia-Pacific Forum on Science Learning and Teaching, Volume 6, Issue 1, Article 1 (June, 2005) Peter HUBBER Explorations of Year 10 students’ conceptual change during instruction
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Introduction
As a practising science and physics secondary school teacher with seventeen years experience in the classroom I consistently found evidence of students’ alternative conceptions in many areas of science and particularly in physics. I found that in spite of my best efforts the traditional teaching strategies employed were not always successful in changing these alternative conceptions. This was the prime motivation for undertaking a research study which essentially was a search not only for a deeper insight into students’ understandings of the world, but also an exploration of different teaching strategies to improve the conceptual understanding of the students.
The literature into students’ understandings of science is substantial (as illustrated by the extensive bibliography by Duit, 2002) and supports my classroom observations. A significant finding of many research studies has been that students’ ideas of the world are often formed before any formal instruction and are often quite different from scientifically accepted ideas. In addition, many studies have found that alternative conceptions are particularly resistant to change, or they change in unexpected ways, within the formal setting of the classroom.
This paper outlines a research study that initially explored the pre-instructional understandings of geometrical optics of a group of Year 10 students. The exploration of students’ understandings continued throughout a teaching sequence that employed strategies that specifically targeted the students’ alternative conceptions. I undertook the dual roles of teacher and researcher.
The theoretical framework that underpins this study is provided by the theory of constructivism. Constructivism, as a theory of learning, recognises that learners construct, rather than absorb, new ideas within the context of their personal knowledge, and they actively generate meaning from experience. Learning is viewed as conceptual change produced by the construction and acceptance of new ideas or the restructuring of existing ideas of the learner.
Constructivism has provided the theoretical base for the exploration of teaching and learning approaches that establishes the need to directly address the extant knowledge of the individual if any conceptual change is to take place (Posner, Strike, Hewson & Gertzog, 1982). This has led to teaching and learning strategies that allow students to engage in the construction of knowledge from the perspective of their own conceptual frameworks. In contrast, teaching and learning strategies based on traditional approaches of direct instruction have not recognised the need to take the students' present ideas into account when trying to change them.
Constructivist-informed teaching approaches to the process of learning are viewed as activities that explicitly aim to help students to make the constructions that lead to a conceptual understanding of the scientific points of view (Treagust, Duit & Fraser, 1996). Within such approaches students are active learners who come to the classroom with prior notions of natural phenomena that they use to make sense of their everyday experiences (Laverty & McGarvey, 1991). As students actively make sense of the world by constructing and reconstructing their own viable meanings (von Glaserfeld, 1989), constructivist-informed teaching approaches then become a matter of creating situations in which students actively participate in activities that enable them to make their own viable explanations of their sensory experiences (Wood, 1995). A number of research studies (Fetherstonhaugh & Treagust, 1992; Lederman, Gess-Newsome & Zeidler, 1993; Confrey, 1990) have noted a lack of research into the implementation of constructivist-informed teaching and learning approaches within the classroom while Duit (1995) has suggested that "more research is necessary to investigate whether constructivist teaching sequences really result in constructivist learning processes" (p. 280).
The constructivist-informed teaching and learning strategies used in the teaching sequence followed a model of conceptual change developed by Driver and Oldham (1986). This involves an initial orientation stage to give students opportunities to develop a sense of purpose and motivation for learning the topic. After orientation, there is a stage where different ideas are elicited through bringing to conscious awareness the students' own ideas. Through the clarification and exchange of different ideas a stage may be reached where some students need to reconstruct new ideas. This reconstruction of ideas may require student exposure to conflict situations that, in turn, may require a time for evaluation and then the opportunity to apply new ideas to a variety of situations. Finally, any restructuring of ideas requires students to reflect on how their ideas have changed.
The call for more research into constructivist-informed teaching and learning approaches is particularly relevant in the area of secondary school optics. A significant number of studies have explored the way individuals understand optical phenomena at different ages and backgrounds (Galili, 1996). A major finding of the accumulated data from these studies is the occurrence of alternative conceptions of optical phenomena that have been resilient to change through formal instruction in the classroom. Research into students' understandings of optics has also pointed to constructivist-informed approaches as a means to address the central concepts of optics, which this study sought to do.
Copyright (C) 2005 HKIEd APFSLT. Volume 6, Issue 1, Article 1 (June, 2005). All Rights Reserved.