Promotion of Students' Learning of Science through Generation and Evaluation of Analogies : The Case of "Images with a Convex Lens" in Secondary Science

Abstract

This paper presents promotion of students' scientific understanding of "images with a convex lens" in secondary science classes through the generation and evaluation of analogies. Further, the effects of instructions that emphasize "transformation" as a methodological principle for generating and using analogies are explored. Questionnaires were used for examining these aspects. Consequently, the results revealed the points listed below. (1) When students tried to solve a novel problem, they generated an analogy spontaneously. However, the base case of this analogy was familiar to the students, and from a scientific point of view, it was a specific case in the science of lenses. In addition. they did not understand the case enough to solve the problem. There was a difference in the content of the derived conclusions, but this analogical reasoning process was common to them. (2) Given the situation that students had not learned the general principle of images with convex lenses, they used an individual case as a model of problem solving for images with convex lenses. In this situation, it was found that analogies were generated through "transformation," which is considered a cognitive process that modifies the original case, thereby changing one or more features that were previously assumed to be fixed, and finally, identifies the other case. (3) "What-if analysis" is a technique for making speculations about or changing one or more of the properties or factors associated with the base case/target case of an analogy. What-if analysis as a teaching strategy was effective in evaluating the analogies generated by the students. (4) It was suggested that this process of learning science, wherein students generate and evaluate analogies, and learn concept of image point promote the generalization or application of learning content; further, both an understanding of the base case and the target case of the analogies improved.