The objective of this project is to design, implement and evaluate a model for primary mathematics instruction (grades K-3) to enhance student understanding and support teacher change in predominantly minority public schools. The "pedagogical content knowledge," mathematical content knowledge, and beliefs of teachers of minority children will be addressed in summer inservice programs designed to reflect a grade-related focus. The summer component will compel the teachers to: investigate the premise that mathematics instruction should be based on a child's existing knowledge, reflect on their perception of mathematics and mathematical instruction, focus on the influence of affective behavior in instruction, directly address equity issues, examine and develop instructional activities to foster mathematical understanding and problem solving, and experience organizing and conducting meaningful mathematics instruction with a small group of minority children. Project research will be in terms of longitudinal effect on students' mathematical understandings, teachers' instructional approaches, classroom practices, and teacher beliefs. This will include an on-going process evaluation of the implementation of the summer inservice goals and a multi-year impact evaluation of the inservice effects in terms of student learning and teacher beliefs and practices. This project is jointly supported by the Division of Teacher Preparation and Enhancement and the Division of Materials Development, Research and Informal Science Education.