Zeroの文脈に基づく豆電球回路教材が中学生の認識に及ぼす影響 How Does a Bulb Circuit Material with Zero Context Affect Students' Cognition?
The received wisdom is that the conception of the direction and magnitude of an electric current is difficult for students to understand. We have reported that females' cognitive motivation and interest are lower than males' when they learn an electrical unit, which is a serious situation. A science textbook has included "convention context" in lower secondary school in Japan since 1984. Convention context consists of an electrical series and a parallel circuit connecting two bulbs, two dry cells, a circuit switch, and leads. The bulb (3.8V-0.3A) is brighter than the other bulb (2.5V-0.3A) on the series circuit. We plan "zero context" which consists of these circuits connected to a different standard bulb from convention context. The only bulb (3.8V-0.3A) lights on the series circuit (the other bulb: 2.5V-0.5A). The purpose of this study is to obtain how zero context affects students' cognition. 320 first grade lower secondary school students who had not studied electricity since entering the school answered either context questionnaire in the same sequence. We obtained the following results: Zero context has a stronger positive effect on cognitive motivation than convention, which is an improvement on the students' serious condition. However, zero context also makes the context-dependency of students who already have context-dependency heavier. Students are able to examine their established conceptualizations more deeply, but zero context may make it more difficult for students to reconceptualize or correct some mistaken models to a correct one. If students can not only merely memorize the correct conception but also explain the difference in the brightness of bulbs in the electrical circuits using the conception of the principles of the direction and magnitude of an electric current, voltage, and resistance, they who have context-dependency may memorize the correct conception as strongly as those who do not depend on context. This is a problem. Although some teachers have used zero context in science classes, they should use it after solving the problem.
日本理科教育学会理科教育学研究 53(2), 305-316, 2012-11