A map from the Massachusetts Department of Public Health showing the levels of COVID-19 in communities. Green means fewer than 4 cases per 100,000, yellow between 4 and 8 per 100,000 and red more than 8 per 100,000. Grey is less than 4 per 100,000. If the COVID-19 rates were they same as they are this week, Superintendent Dede Galdston told the School Committee Monday that the Watertown will start in-person hybrid classes in late October for the elementary students, late November for the middle and high school. The Watertown Public Schools decided in August that the first day of school will be on Sept.