DES MOINES, Iowa (AP) — Des Moines Public Schools, Iowa’s largest school district, will cancel all classes and activities for at least 17 days starting Friday evening. In a letter sent to staff, Superintendent Thomas Ahart announced Thursday that classes wouldn’t immediately return after spring break next week.

Ahart expressed hope that classes could resume March 30 but given the “dynamic situation,” officials would have to adjust as needed. The move will effect the district’s 33,000 students and 5,000 employees. The school district’s decision comes as many colleges are taking similar actions.