A statewide collaborative in Michigan requests 48 months funding to train 150 middle school mathematics teacher leaders. Seventy-five, six-person leadership teams will be selected from 75 districts to lead their respective districts to implement NSF-developed exemplary middle school mathematics programs through a school professional development plan. Each team will consist of two middle school mathematics teachers, one high school mathematics teacher, one administrator, and at least one community member. The leadership team will develop school action plans in two one-day professional development meetings. In years 2-4 the middle school teachers will attend two-week summer workshops, and six one-day workshops each year. They will also offer six one-hour professional development programs to the school mathematics teachers each year.