ABSTRACT
Current cognitive theory and research stress the centrality of knowledge representations of an individual for learning and behavior. As in all cognitive theories, these knowledge representations are assumed to influence perception, attention, thinking, learning, problem solving, and behavior in a variety of ways. In some ways, understanding the acquisition and change in the knowledge base of an individual is the central question in cognitive development. Of course, there are many different models of knowledge acquisition and change (cf. Keil, 1998; Wellman & Gelman, 1998), but in teaching and learning contexts general models of conceptual change have been fruitful and useful (e.g., Chi, Slotta, & de Leeuw, 1994; Dole & Sinatra, 1998; Gardner, 1991; Pintrich, Marx, & Boyle, 1993; Strike & Posner, 1992).
