We examine the role of school closures in contributing to the negative labor market impacts of the COVID-19 pandemic. We collect detailed daily information on school closures at the school-district level, which we merge to individual level data on various employment and socio- demographic characteristics from the monthly Current Population Survey from January 2019 through May 2020. Using a difference-in-differences estimation approach, we gauge how the intensity of school closures affects the labor supply of mothers and fathers of young school-age children. We find evidence of non-negligible labor supply reductions, particularly among mothers. These impacts prove robust to endogeneity checks and persist after accounting for other social-distancing measures in place.