| Summary: | Many students currently entering college are able to solve mathematical problems but often do not understand the chemistry concepts underlying their calculations. High school chemistry teachers from Texas and the United States (US) were surveyed as to what topics they teach in their chemistry classes. A subset of Texas teachers was also interviewed about their instruction. The survey indicated that less-experienced Texas teachers are omitting a number of topics from their chemistry instruction, as compared to more experienced teachers. No differences were seen for those topics among US teachers. Chemistry textbooks from 1930 to the current 2002 Texas state adoptions were analyzed for inclusion of these topics. The only textbooks that were missing topics were from the 1930s. All others contained the topics. In general, textbooks have been increasing numbers of questions and problems for each topic, with the number of quantitative problems increasing at a greater rate than qualitative problems. Analysis of interview transcripts revealed that the main reason for omission of topics by less-experienced Texas chemistry teachers is that these topics are not assessed on the Texas Assessment of Knowledge and Skills science exam. Omitted topics were both qualitative and quantitative; the common factor is that they are not tested. School administrators reportedly reinforce this practice. Archival data regarding textbook usage by general chemistry students showed that students' course grades are not correlated to the amount of time they spend using their textbook. With topics included in textbooks, and no relationship between textbook usage and student grades, observed changes in chemistry courses must be due to changes in classroom instruction. With new course standards adopted by Texas for chemistry and the development of end-of-course exams, these changes should produce graduates who understand chemistry concepts as well as they solve mathematical chemistry problems. Repeating this study in 5 years may show that increasing the amount of chemistry tested will produce students entering college with a better conceptual background in chemistry.
|
|---|
