The Full Option Science System (FOSS) is a new concept in elementary school science education proposed by the Lawrence Hall of Science. FOSS will be an integrated teacher-education program and classroom instructional package for general education in grades 3 through 6. The instructional package will be based on tested, reliable pilot activities: the SAVI/SELPH (Science Activities for the Visually Impaired, and Science Enrichment for Learners with Physical Handicaps). The teacher education component will be based on pilot coursework used at the Lawrence Hall of Science. The materials used to prepare teachers to be effective, confident science teachers will be the same materials used in the classroom to teach students. Products of the project will include mini-units of hands-on activities covering a broad range of science topics, student equipment and teacher's guides, and a number of supporting documents. Research into two important aspects of science instruction will also be conducted. The project will focus on the problem of delivery and management of student equipment and on the factors that encourage the replication and perpetuation of teacher education activities.