This project builds on Phase I of the Interactive Mathematics Project. A new three-year high school mathematics curriculum, which embodies the NCTM Standards was developed, pilot tested, and two years field tested with diverse populations during Phase I. This new secondary mathematics curriculum eliminates tracking compleely and has proven to be effective with all students at all students at all levels. Phase II builds on the work of Phase I by developing a fourth year curriculum; reexamining and then revising all three years with the goal of improving continuity; writing supplementary materials to allow greater teacher flexibility in meeting the wide range of student needs; conducting a thorough evaluation of the effectiveness of the curriculum; assessing the various models of teacher inservice; and disseminating the program widely through large regional centers.