This study was designed to investigate the effect on teachers and their students of a model of professional development that immerses teachers in scientific inquiry appropriate to their classrooms while modeling the use of reform-based pedagogical strategies for teaching science. The course was designed and team taught as a collaborative effort between scientists and science educators. Quantitative data were collected on teachers' pre and post course science content knowledge, attitudes toward science, and science process skills. Quantitative data on the process skills and attitudes toward science of students of project participants and matched groups of students and teachers not participating in the project were collected and compared. Qualitative data from open-ended questionnaires, journals, and learning logs were collected from both students and teachers. The program was found to have a statistically significant impact on teachers, their classrooms, and their students. It is recommended that future science professional development projects incorporate collaboration between scientists and science educators. These collaborative efforts should focus on integrating scientific investigations designed and carried out by participants with appropriate pedagogical models for incorporating inquiry-based learning in the classroom. Contains 16 references. (Author)