The Maryland Board of Education voted Thursday in favor of a statewide mask mandate for all public schools.
Currently, state school districts can make their own decisions on whether to require or recommend masks; most do require them, but they are optional in five counties.
As the delta variant continues spreading rapidly across the country, causing a new wave of infections and hospitalizations, it is sending school administrators scrambling to adjust reopening plans.
The vote provides a standard set of rules as students across the state prepare to head back into classrooms in person.
State senators expressed support for the mandate, which will need to be approved by a legislative committee in the General Assembly before it takes effect.
Senate President Bill Ferguson (D) in a statement said the vote "recognizes the importance of safely keeping Maryland students in the classroom through proven mitigation strategies." Ferguson said he will work quickly to make sure the measure passes.
Schools in neighboring Virginia and the District of Columbia already require masks.
Schools have become the latest battleground in the fight over coronavirus safety. In states where schools opened earlier this month without mask mandates, tens of thousands of children have been quarantined.
Meanwhile, local districts in states such as Florida, Arizona and Texas are at war with their GOP governors over the refusal to allow mask requirements.
Maryland's mandate can only be in effect for 180 days before it expires because of its emergency status.