The Development of Students’ Understanding of the Conservation of Mass in a Water Solution through the Presentation of Contrasting Materials

Abstract

The purposes of this paper are the next two points. First, to make clear how the use of contrasting materials is the most effective way to teach the target material, we examained the development of students’ understanding fo the conservation of mass in a water solution through the presentation of several contrasting materials at the same time. Next, in accordance with this result, we proposed a teaching strategy and verified its efficacy. As a result, the findings of this study are as follows: (1) The most effective material to demonstrate the conservation of mass in a water solution is clay. (2) However, the use of clay by itself is not sufficient for the demonstration of this concept. (3) The class introducing the teaching strategy of using contrasting materials such as sand and wood at the same time was effective.