The research has three purposes. The first is to describe the way in which experienced high school biology, chemistry, and physics teachers think about their discipline, their students, and their teaching. The second is to identify relationships between the teachers' thinking, their planning and teaching practices, and the conceptual learning of students in their classrooms. The third is to develop techniques of video data collection in high school science classrooms and computer- based video and audio data analysis to support the above purposes. In a pilot study, video data collection and computer-based analysis procedures will be developed and refined by observing three teachers, one in each discipline. In the full study eighteen teachers will be studied, six in each discipline. Each teacher will be observed teaching three target units each of about 2 weeks duration. Each teacher will also be interviewed at intervals throughout the project; at the start and end of the study about the way they think about teaching science to high school students, at the end of each unit to clarify classroom events, and in the final year of the project to provide feedback about the analysis of data. Finally, each class of students will be given a pre-test and post-test for each unit. This research will provide information about different ways in which eperienced teachers think about the nature of their discipline, the ways in which their students learn science, and the effect this has on instruction. Further, it will describe various patterns of practice; ways in which teachers' thoughts relate to their classroom practices and to the conceptual learning of their students. Finally, it will detail similarities and differences in these patterns of practice for biology, chemistry, and physics teachers. These detailed descriptions will provide a level of understanding of science teaching which will significantly enhance the quality of preservice and inservice science teacher education and, ultimely, science teaching in the nation's high schools.
