Instructional Science 29: 45–85, 2001. © 2001 Kluwer Academic Publishers. Printed in the Netherlands. 45 Conceptual change using multiple interpretive perspectives: Two case studies in secondary school chemistry ALLAN G. HARRISON 1 & DAVID F. TREAGUST 2 1 Central Queensland University, North Rockhampton, Queensland, Australia 4702 (e-mail: a.harrison@cqu.edu.au); 2 National Key Centre for School Science and Mathematics, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845 (e-mail: itreagus@info.curtin.edu.au) Received: 27 May 1997; in final form: 6 June 1999; accepted: 4 October 1999 Abstract. Conceptual change is predominantly described as a rational process; however, researchers are beginning to explore alternative explanations for why some students learn but others given the same opportunities do not. New perspectives include social and motivational factors, ontological issues, modelling ability, intellectual development and the question of whether conceptual change is revolutionary or evolutionary. This paper argues that conceptual change is best understood when multiple perspectives are used to interpret chemistry learn- ing. Case studies of two apparently similar students are used to show that personal factors and differing interests and purposes for studying science can significantly influence learning outcomes. The case studies support an argument that high scores on achievement tests are unreliable indicators of conceptual learning and recommend that teachers and researchers pay more attention to qualitative indicators of learning such as students’ conceptual status, modelling level and intellectual position. The findings suggest that teachers and curriculum developers should take into account the qualitative differences that studies such as this identify. Keywords: conceptual change, multiple interpretive perspectives, epistemology, ontology, social/motivational issues, modelling ability, intellectual development, atomic models Introduction The bangs, colours, stinks and wonder of chemistry attract many high school students but understanding macroscopic changes as particulate action is conceptually daunting. Gabel et al. (1992) and Johnstone (1991) describe three levels at which chemical concepts can be taught and learned, namely, sensory (macroscopic), atomic/molecular (submicroscopic) and symbolic (formulae and algorithms). Researchers have found that many students try to explain particle behaviour using macroscopic analogs; for instance Ingham’s (1991) subjects believed that atoms were coloured like the balls in molecular 1 Phone: 61 7 4930 9512; Fax: 61 7 4930 9604. 2 Phone: 61 8 9266 7924; Fax: 61 8 9266 2503.