Material Cycles in Nature. A New Approach to Teaching Photosynthesis in Junior High School

Abstract

PHOTOSYNTHESIS is perceived by most teachers to be one of the most problematic concepts in biology (Finely, Stewart & Yarruch 1982; Johnstone & Mahmoud 1980). Many researchers of students' misconceptions in biology have chosen to concentrate on photosynthesis and related concepts (Barker 1985; Bell & Brook 1984; Eisen & Stavy 1988; Simpson & Arnold 1982; Smith & Anderson 1986; Stavy, Eisen & Yaakobi 1987; Wandersee 1983). Some of them subsequently developed study units to help teachers overcome these difficulties (Barker 1986; Bell 1985; Bishop, Roth & Anderson 1986; Simpson & Arnold 1986). Simpson and Arnold (1986) emphasize an understanding of certain concepts prior to teaching photosynthesis. They suggest that teachers start with a short review of the concepts of living things, gases, food and energy. Bell and her colleagues in Leeds believe that, If students are to be helped to change their existing ideas towards the currently accepted school science ideas, then their existing (and alternative) ideas may need to be given attention. Bishop, Roth & Anderson (1986) developed a teaching module on respiration and photosynthesis, hoping to overcome students' confusion between photosynthesis and respiration. Barker (1986) deals with the question of where does the wood come from? by addressing such misconceptions as: plants inhale carbon dioxide and exhale oxygen, feed on minerals and fertilizer, etc. We would like to suggest a different approach to the teaching of photosynthesis. This paper describes the current approach in Israel and our findings on the difficulties children have in understanding photsynthesis. Then we present the foundations of our approach, followed by our recommendations.