The Science Connections Project is a five-year professional development program for 320 middle schools science teachers in the county system. The goal is to extend the revised elementary science program into middle schools and to provide the professional development at the middle school level. The project, in cooperation with the University of Maryland, The American Physical Society, and the National Institutes of Health provides intensive training for middle school science teachers, Grades 6-8, so that students who were taught by elementary teachers participating in the NSF funded elementary teacher enhancement project continue to develop science literacy skills and knowledge using inquiry-based and constructivist-based learning. The middle school science teachers receive professional development in science content; and instructional pedagogy, which includes a constructivist approach, cooperative learning, and inquiry-based teaching; performance teaching and assessment; and technology applications. An action research model will be used to promote permanent and ongoing change in teachers' professional development.