内包量概念に関する児童の本質的なつまずきとその修正

抄録

Whereas Piaget established conservation task to asess children's understanding of extensive quantity, this study aimed at establishing another kind of conservation task to asess children's understanding of intensive quantity, e.g. the concept of density. The following study examined children's misconception of density by using our conservation task. Subjects were sixth graders. A typical question was asked in the conservation task: Which density is greater, a big or a small aluminium lump? Although subjects were taught in advance that density of substance was given by its weight per unit volume (1 cm3), commonly explained in school education, half of the subjects failed to answer the question. They answered that the density was greater for the big lump, suggesting they did not understand the concept of density by a commonly given definition. Results were discussed from the viewpoint of the formation process of intensive quantity concept. A teaching method to lead children to a better understanding of the nature of intensive quantity was proposed.