The sudden closure of kindergarten through 12th grade (K-12) schools nationwide this spring likely helped to avert a medical catastrophe from the coronavirus disease 2019 (COVID-19) pandemic. This decisive step, however, is casting a long shadow. By the time the school year ends in June, more than 55 million US children will have missed months of in-class instruction.1 The educational effect to date represents only one dimension of the harm to children.