9353423 Hestenes This national leadership project will directly serve 168 physics teachers. The project is based on a new paradigm for physics instruction, the Modeling Method. In Phase I, each of two 6-week summer workshops will enroll 24 physics teachers. The following summer all teachers return for another 6-week workshop. Ten of these 48 teachers will be selected as Workshop Leaders for Phase II. In Phase II, beginning in the third summer, five 5-week workshops will be conducted by two person teams from the ten Workshop Leaders. Each will enroll 24 physics teachers. This second wave of teachers will attend a second 5-week workshop the following summer. From these 120 teachers 50 will be selected as new Workshop Leaders. In Phase III, the 60 Workshop Leaders will each conduct a 6-week workshop for 24 physics teachers covering the entire curriculum, using the modeling method. Participants must teach at least one section of physics following their participation in the summer workshops so they can use the modeling method in their classroom the following academic year. The workshops in Phase I are at Arizona State University and Chicago. In both Phase I and Phase II participants can earn graduate credits. Cost sharing equals 120% of the NSF award. ***