Yes, public elementary and secondary (K-12) schools throughout the Commonwealth of Massachusetts are closed in observance of Patriots' Day. It is an official state holiday mandated by law, occurring annually on the third Monday in April.
This observance is codified in Massachusetts General Laws, Chapter 6, which designates the day as a legal holiday. Consequently, all public schools, as well as state, county, and municipal offices, are required to close. The academic calendars for private schools, colleges, and universities, however, are determined by their own governing bodies. While many private institutions and universities also cancel classes, particularly those located along the Boston Marathon route, they are not legally obligated to do so.
Therefore, while closure is standard for the public K-12 system, students and staff at private or post-secondary institutions should always verify their specific institution's academic calendar. The widespread closure is also a practical response to the major civic events held on this day, which cause significant travel and logistical disruptions across many communities.