The Warren Consolidated Schools district will be closed Tuesday as many teachers say they will be absent.
Superintendent Robert Livernois said there will be no school for all grades.
"While I understand this is somewhat unusual, my number one priority is student safety and without an adequate number of staff members, we cannot hold school," said Livernois in a statement to the community.
The teachers may be planning to attend rallies in Lansing against state lawmakers' push for right-to-work in Michigan.
Related: Taylor schools to close Tuesday for lack of teachers
Take a look: Complete list of school closings
Warren Consolidate is not the only Metro Detroit school district with a high number of teachers planning not to show up Tuesday. The Taylor School District also will be closed Tuesday because staff members have either called in sick or are taking personal days.
The Michigan state House and Senate approved bills last week that would prohibit requiring non-union employees to financially support unions at their workplace.
Lansing authorities are bracing for an onslaught of protesters Tuesday. They have increased police presence and plan road closings and parking restrictions around the Capitol.