This document presents an overview of the Biological Sciences Curriculum Study (BSCS) Teacher Development Modules for Elementary School Science. It documents the collaboration of BSCS with science educators, science supervisors, and outstanding science teachers in developing, evaluating, refining, and disseminating four teacher development modules to support the improvement of science teaching in the elementary school. The modules are based on the major themes of the contemporary reform in science education: innovative instruction (constructivism, cooperative learning, and learning styles), curriculum emphases (thematic, less-is-more, and science-technology-society), equitable teaching, and alternative assessment. Subtopics include the nature of science and technology, major science concepts, classroom management, and educational technology. The population that conducted the content review process for the modules included project staff, members of the advisory board, university faculty, teachers, and science supervisors. It is reported that overall, reviewers and teachers responded very positively to the modules and voiced the need for such materials for both inservice and preservice teachers. Contains 60 references. (JRH)