Despite data-driven decision making being a ubiquitous part of policy and school reform efforts, little is known about how teachers use data for instructional decision making. Drawing on data from a qualitative case study of four elementary schools, we examine the logic and patterns of teacher decision making about differentiation and ability…

Secondary school tracking is organized in some countries on a course-by-course basis within schools and in other countries as explicit academic and vocational streaming, often in separate school buildings. This article is the first to compare these two forms of tracking, using student-level tracking data across the United States and 19 other…

This study examines the impact of ability grouping practices on the achievement gains among African Americans and Hispanics during elementary school. Using data from the Early Childhood Longitudinal Study, the results strongly support the differential effects hypothesis of ability grouping. That is, students who are lower grouped for reading…