The goal of the project is to improve the mathematical and scientific competence of elementary school students through the development of teacher enhancement models based in professional development schools. A professional development school is defined as a partnership wherein university and school personnel work together as a team to share what they know, discover new knowledge about schooling and explore new models of teaching and learning. The participants will consist of cohorts of 6 leadership teachers from each of 4 school districts. One new cohort will be added in each of the four years. Two "bridge" teachers will co-ordinate the activities between districts. These 26 teachers will participate in weekly 2 hour seminars during 30 weeks of the academic year to enhance their subject field and pedagogical knowledge and learn appropriate modes of working with adult learners. During each of 4 summers the leadership teachers will conduct workshops with teachers within their schools. The "bridge" teachers will link the 4 project schools with the University, each other and eventually other schools in the district. Administrators and parents will be included in the activities to help accomplish change. Cost sharing is 18% of the NSF request.