ASPECTS OF CONSTRUCTIVISM

An experimental setting was used in a class of 23 sixth-grade students to prompt discussions about shadows. A rectangular wooden block with an incandescent electric lamp, mounted in the middle of each side, consisted the experimental setting. Additionally, there was a fifth lamp that was positioned exactly above the house and could be removed at any time. Each lamp could be replaced by other lamps of different colours and could be turned on and off independently. A two-dimensional model of a house, made of opaque cardboard, was also mounted upright at the center of the wooden block. The model showed a house with an inclined roof, a chimney, and one door and two windows that were represented using three movable pieces of cardboard. Students were asked to predict the position and other characteristics of the shadow when (a) each one of the five lamps was turned on individually, and (b) two lamps mounted on opposing sides of the wooden block were turned on simultaneously. Discussions were facilitated in order to create cognitive dissonance in students' thinking and support the consequent psychological process of equilibration through a collaborative negotiation of students' diverse understandings. The transcribed discussions were analyzed in an attempt to exemplify the importance of the social interaction between students' knowledge schemes and their experience with the environment (physical and human), as well as aspects of the scientific epistemology and their relevance to conceptual change.