This project will upgrade the content knowledge and teaching skills in the physical and earth sciences of elementary school teachers. The project will provide basic training for elementary school teachers and also produce leaders from each of 24 elementary schools. Phase I consists of an intensive four-week summer workshop. Phase II includes three all-day sessions on Saturdays during the following academic year. In addition, the project staff will visit classrooms of participant teachers at least once during each semester. Phase III will focus on the training of teacher leaders. Phases I and II are designed to help teachers that want and need help with their science background and skills. Phase III is designed to recognize and develop those teachers who are already knowledgeable and deserve additional support. These teacher leaders will serve as on-site resource persons for their respective schools, providing assistance to other teachers.