CHEMISTRY TEACHING IN LOWER SECONDARY SCHOOL WITH METHODS BASED ON: A) PSYCHOLOGICAL THEORIES; B) THE MACRO, REPRESENTATIONAL, AND SUBMICRO LEVELS OF CHEMISTRY

Abstract

Two teaching methods for the improvement of learning of the highly abstract and complex content of chemistry in lower secondary school were studied in this work: a) a method based on developmental psychology, and in particular on some of psychologist R. Case’s proposals; (b) a ‘three-cycle’ method based on the distinction of school chemistry into three levels of approach according to A.H. Johnstone, namely the macroscopic, the representational, and the submicroscopic. The macro cycle did not include chemical notation, as well as the concepts of molecules and atoms. The representational cycle covered the same course material by adding chemical formulae and equations. The submicro cycle introduced atomic and molecular structure, and stoichiometry. Four teaching approaches, for three experimental groups and for one control group were tested. In the experimental groups, (a) some of Case’s suggestions; (b) the three-cycle method; and (c) the combination of these two methods were applied respectively. All groups were subjected to the same evaluation tests at the end of the school year and at the beginning of the next year. The experimental groups scored higher at both tests, mainly on the theoretical questions. The group that followed the combination of Case’s and Johnstone’s suggestions was the best achieving one. Finally, the largest single positive effect was made by the three-cycle method. [Chem. Educ. Res. Pract. Eur.: 2000, 1, 217-226]