This 2.5-year project will develop a school-based model for improving mathematics instruction in grades K-8. A total of 65 elementary and middle school teachers in Brooklyn will participate in a program that combines instruction in mathematics content and methodology, in-school support, mathematics field trips, and citywide Math Forums. During the first year, forty teachers from four schools will take an academic-year mathematics course that will implicitly model sound pedagogical strategy and an education course that explicitly examines such teaching techniques. During the summer, 20 of the teachers (designated as "math enthusiasts") will take an additional three-week course in mathematics content. During the second year, the mathematics and education courses will be offered to 25 more teachers from two additional schools, while the twenty "math enthusiasts" take a course in leadership skills. The latter will serve as leaders in mathematics education in their schools and districts. Project staff will visit each participating school once a week. In addition, the project will sponsor "Math Forums" addressing various aspects of mathematics instruction, publish a newsletter, and prepare resource packets for two mathematics field trips. Evaluation will include assessment of the participants' knowledge of and attitude towards mathematics and observations by the project staff. Brooklyn College is contributing in cost-sharing an amount equal to 110% of the NSF award.