Alliance of Mentors for Physics Instruction: A Teacher Leadership Institute is a joint project of California State Polytechnic University, Pomona and California State University, Fullerton. The project is designed to train 42 experienced high school physics teachers with strong backgrounds in physics in content and leadership training in the seven-County Southern California metropolitan area and to develop and establish this group as an Alliance of mentors to be used as a resource for other teachers. The focus of the content training will be modern physics concept enhancement along with directed studies in the incorporation of modern physics topics throughout the classical high school curriculum. There will be three residential summer institutes, during which content enhancement will be performed with lecture presentations, laboratory experiences, computer technology training (using Interactive Physics, Physics Explorer and other software), guest presentations and problem solving sessions. In addition to these activities, summer institutes will include leadership training, preparation and design of academic year workshops and development of strand activities described below. Academic year activities will include professional development workshops offered through County Offices of Education, during which mentors will disseminate content and strategies to additional physic teachers. These workshops will be of two types: 1) Modern Physics Workshops, designed for experienced physics teachers and aimed at passing on strategies for incorporating modern physics into the high school curriculum; and 2) Conceptual Physics Workshops, designed for junior high school teachers, new high school teachers and crossover teachers, and focused on building strength in fundamental concepts in physics. In addition, each mentor will be responsible for pursuing professional development activities in one of three "strands": 1) Elementary In-Service Strand, in which participants will work with the California Science Implementation Network (associated with the California State Systemic Initiative) in improving the abilities of elementary school teachers to teach physical science; 2) Research Strand, in which participants will establish and implement an educational research project at their local site; or 3) Scope, Sequence and Coordination In-Service Strand, in which participants will work with California Scope, Sequence and Coordination (SSC) representatives in assisting SSC teachers in their abilities to teach integrated science. The mentors will attend Topical Conferences on three academic year Saturdays each year, at which research scientists will share information in morning presentations about applications of physics in the research world. In addition, all high school physics teachers in Southern California will be invited to attend these Conferences. In the afternoons of these days, the mentors will hold meetings designed to share information about workshop and strand activities and maintain networking relationships. These networking relationships will be further enhanced through a link to CSUNET, an existing computer network that links the California State University campuses. The mentors' strand activities will form the basis of a thesis project. After completing the three-year program, mentors in the Alliance will be eligible for a Master of Arts in Teaching Science degree, using their thesis project in conjunction withcontent enhancement from the summer institutes and a series of science education courses offered along with the summer institutes. The PI for the project is Dr. John Jewett of CSU-Pomona. Cost-sharing equals 29% of the NSF award.