# COVID-19–Related School Closures and Learning Modality Changes — United States, August 1–September 17, 2021

> Research article (MMWR Morbidity and Mortality Weekly Report, 2021) · cited 47× · AI/ML

**Wikidata**: [openalex:W3203876248](https://www.wikidata.org/wiki/openalex:W3203876248)  
**Source**: https://4ort.xyz/entity/covid-19related-school-closures-and-learning-modality-changes-united-states-august-1september-17-2021