This 5-year project focuses on critical needs in teaching undergraduate science to all diverse majors with emphasis on the preparation and long-term development of pre-service, undergraduate, K-6 teachers of science. The goal is to investigate the impact on these students of undergraduate, standards-based, reform entry-level science courses developed by faculty that are different from traditional courses. Thirty reform and 30 comparison undergraduate science courses from a national population of 103 diverse institutions, stratified by institutional type, will be selected and compared in a professional development impact design model. Data will be collected using multiple quantitative and qualitative instruments and analyzed using comparative and relational studies at multiple points in the impact design model. Criteria for success of the project will be determined by conclusions drawn from the research questions; including evidence and effect sizes of short-term impacts on all undergraduate students and long-term effects on graduated in-service teachers in their own classroom science teaching; identification of characteristics of reform courses that produce significant impacts; identification of characteristics of effective faculty, and effective dissemination.