Teaching chemistry concepts through multiple analogies

Abstract

One of the most important challenges faced in science teaching is students' preexisting conceptions about the concepts and phenomena they are taught. These conceptions typically diverge from school science and should be taken into consideration by science teachers when negotiating the construction of scientific knowledge in the classroom. Analogies are a particularly powerful tool for science teaching, since they allow comparison and mapping between different knowledge domains: the source (a domain familiar to the learner) and the target (the domain to be taught and understood by the learner), thus supporting the construction of new knowledge. This study proposes an introductory chemistry teaching sequence about the concepts of chemical element and chemical compound by means of multiple analogies, designed so as to take into account students' alternative conceptions. An experimental design involving pretests and posttests with two groups of eigth grade students attending a public secondary school in Greece was implemented, comprising a teaching intervention using multiple analogies with the experimental group and a conventional approach with the control group. Results indicate that the participants in the experimental group achieved significantly higher scores in the posttest than their counterparts in the control group. Their responses reflected a significant improvement in their understanding of critical aspects of the taught concepts, concerning the distinction between chemical element and chemical compound as well as between chemical compound and mixture. Moreover, they exhibited a better understanding of a variety of characteristic properties of matter. Implications for teaching of fundamental chemistry concepts with the use of multiple analogies are discussed. © Common Ground Research Networks, Vasilia Christidou, Marianna Theodosiou, Vassilia Hatzinikita.