Heat has closed Baltimore City, County schools this spring. Here’s what to know about the status of air conditioning.

The lack of air conditioning in Baltimore City and Baltimore County schools has forced in-person lessons to go online this spring — most recently last week — as school systems continue to struggle with high temperatures in their oldest buildings. Long after most school systems in the state had installed air conditioning in all their buildings, Baltimore City and Baltimore County still have dozens of buildings where temperatures rise above comfortable levels.