Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
School scheduling systems are frequently at the forefront of policy discussions around the world. This paper provides the first causal evidence of student performance during double-shift schooling systems. We exploit a six-year quasi-experiment from a country in Eastern Europe where students alternated between morning and afternoon school blocks every month. We estimate models with student–class and month fixed effects using data on over 260,000 assignment-level grades. We find a small, precisely estimated drop in student performance during afternoon blocks.