Delayed learning to read and write during the COVID-19 pandemic: longitudinal study of the heterogeneous effects on all first graders in France

In March 2020, schools in France closed for two months due to the COVID-19 pandemic. Using data from the national assessments, we measure the impact of this unprecedented crisis on the learning of 800,000 students who were in first grade during the school closures. We show that students' learning progress dropped after the lockdown by 10% standard deviation from a normal year in mathematics, and even more dramatically in French with a decrease of 15% standard deviation. The crisis exacerbated pre-existing inequalities since students from disadvantaged schools were the most affected. We also find that the effects are particularly strong in domains where the school plays a fundamental role in reducing social inequalities in early learning, namely reading and writing.