COMPUTERIZED MOLECULAR MODELING AS A TOOL TO IMPROVE CHEMISTRY TEACHING

The use of molecular models to illustrate and explore phenomena in che mistry teaching is widespread. However, only one type of model is usua lly used, and not enough emphasis is put on its meaning. The advantage of computerized molecular modeling (CMM) stems from the convenience a nd simplicity of building molecules of any size and color in a number of presentations. To expose chemistry teachers to the use of CMM we de veloped a 14 h workshop on models. It consists of an introduction to t he model concept, using various types of models (including CMM) and ex periencing ways to use them for illustrating chemical structure and bo nding via team projects. This workshop has been incorporated into pre- and in-service training at the Department of Education in Technology and Science at the Technion since 1994. As a final project, teachers w ere asked to plan a session of 1-2 lessons by building a miniature dat abase of molecules along with working instructions. The new methodolog y is based on using CMM through a special booklet, designed in a const ructivist approach. During 1995, it was implemented in three tenth gra de experimental classes with two other classes serving as a control gr oup. Overall, teachers' attitudes toward using molecular modeling to i mprove chemistry teaching were favorable. The effect of using molecula r modeling on students' understanding and constructing new concepts wa s investigated in relation to chemical structure and bonding as well a s to geometric and symbolic representation. In two representative ques tions related to three-dimensional molecule structure, the experimenta l group performed better than the control group. Students' attitudes t oward the use of CMM have also been found to be positive. Most of the students enjoyed using the new methodology and indicated it helped the m understand concepts in molecular geometry and bonding.