ABSTRACT
Conceptual change has perplexed and intrigued researchers at least since Rousseau (1892) and Locke (1824). When Piaget published his account of child development (Piaget, 1953, 1970), he brought extensive evidence of student thinking into the conversation, drawing attention to the ideas students develop spontaneously and arguing for biological constraints on reasoning. Subsequent researchers have explored various constraints in logic or processing capacity and have also analyzed the nature of the ideas that students devise to explain the scientifi c phenomena they encounter both in and out of school (diSessa, 1988; Linn, 1995; Siegler, 1996).
