Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Despite its relevance for policy, there is limited evidence on the impact of lowering school entry age and increasing the length of primary education on student performance. This study examines these changes in the context of Brazil’s 2006 compulsory schooling reform. We exploit differences in the years that schools adopted the policy as a plausibly exogenous source of variation and use students’ birth months to predict school entry age. The overall impact of the policy package was to increase math and Portuguese test scores by approximately 0.11 and 0.06 standard deviations in students’ fifth and ninth year of school. Among the students who entered primary school one year earlier, those without any prior education experienced larger increases in their fifth year test scores compared to students who gained an additional year of primary education at the expense of preschool. This advantage, however, became smaller by their ninth year. We discuss different mechanisms through which the policy may have influenced student performance and conduct various robustness checks that lend support to the paper’s interpretation.