Academic achievement across the day: Evidence from randomized class schedules

Abstract

This study expands our understanding of how school day schedules affect achievement. We focus on three aspects related to scheduling: student fatigue, time of instruction, and instructor schedules. Data cover five academic years at the United States Air Force Academy, where schedules are randomized, grading is standardized, and there is substantial variance in schedule structure. Analyzing over 180,000 student-course outcomes, we find causal evidence of cognitive fatigue brought on by scheduling multiple courses in a row. The expected performance of two students in the same class may differ by as much as 0.15 standard deviations simply owing to their prior schedules. All else equal, students perform better in the afternoon than in the early morning. We also note that instruction improves with repetition. Heterogeneous effects by ability suggest that overall gains are possible. Prioritizing certain schedules would be equivalent to improving teacher quality by one-third of a standard deviation. A reorganization of students’ daily school schedules is a promising and potentially low-cost educational intervention.