Sixty-Two school districts, constituting 34% of the 178 school districts in Colorado, serving 2.7% of students, utilize the four-day week as the structure for organizing their school year. This paper is intended as an overview of the practice. Actual practices differ from district to district.

This report compares the academic achievement and student growth of the four-day districts to the academic achievement of five-day districts of similar size. Overall, the results indicate that both groups of districts perform similarly on the state assessments and that their students show very similar amounts of academic growth as reflected by the Colorado Growth Model.