To understand how assessment, particularly alternative assessment, and practice interactions may differ among schools with different implementation contexts and different school cultures, this project is studying over time a set of schools representing different state and local policy contexts and including different student populations. Research questions are: (1) whether the implementation strategies facilitate or inhibit teacher use of information from alternative assessments; (2) how alternative assessments interact with teachers' perceptions of achievement and student ability; (3) how alternative assessments interact with teachers' instructional decisions; (4) how alternative assessments interact with students' perceptions of performance and abilities; and (5) how each of the above differs in different schools. Longitudinal case-study methods are being used in two phases. In phase 1, four sites in California are being studied; phase 2 may expand to include other schools and states. The project will result in a series of products that should enhance the understanding of policymakers, researchers, and practitioners about ways to implement alternative assessments to improve learning and teaching. One table summarizes the study framework. There is a 35-item list of references. (SLD)