Draft

This study investigated mathematics learning at a suburban United States high school that simultaneously adopted a semestered (4 x 4) block schedule and the Interactive Mathematics Program (IMP), a curriculum designed to implement the National Council of Teachers of Mathematics (NCTM) Standards. Previous research has often found that at sites where a block schedule was adopted without changes to mathematics curriculum and instruction, mathematics achievement has declined. In contrast, when a semestered block schedule and the IMP curriculum were implemented jointly, with extra time allocated to planning and staff development, the two innovations were followed by improvements in student mathematics achievement