A Baltimore parent picks up her children at Franklin Square Elementary/Middle School in May, when high temperatures also led to an early release.
CNN  — 

With the school year starting Monday, almost two dozen schools in the Baltimore City Public School system are dismissing early a few days this week because they have no air conditioning.

The Baltimore area is expected to hit 93 degrees Monday, with the heat index reaching triple digits Monday and Tuesday, according to the National Weather Service in Baltimore and Washington, DC.

At least 15 schools in the district are considered “traditional,” meaning they lack air conditioning systems, and five schools have air conditioning systems that need to be repaired, a release from the district says.

Two schools whose buildings are not owned by the district also will have early release, the district said.

The district has dismissed schools early several times in recent years because of heat, according to CNN affiliate WMAR. And with climate change bringing hotter days, several other schools are facing the same problem.

Teachers went on strike in Columbus, Ohio, last week to protest classroom conditions, including a lack of air conditioning in some rooms.

“Students move around to different buildings, like a college campus, and they never know from one classroom to the next if it’s going to be 50 degrees or 90 degrees,” Courtney Johnson, a school library media specialist in Columbus, told CNN’s Victor Blackwell.

Some schools don’t have any air conditioning, she said, or may only have “a couple of rooms” with it. And in schools that do have it, including where Johnson works, the systems need fixing, she said.

“That’s what we’re fighting for – safe, properly maintained and fully resourced schools where the air conditioning and heating works, and students don’t have to suffer,” Johnson said.

CNN affiliate WGNX reported there were hundreds of open HVAC issues at Clayton County, Georgia, schools when students went back to classrooms earlier this month.

The Philadelphia School District said in June it has about 100 school buildings with insufficient air conditioning.

It’s not clear how widespread the problem is – the National Center for Education Statistics last Condition of America’s Public School Facilities report is from 10 years ago, when almost a third of public schools with permanent buildings were reported to have fair or poor air conditioning and heating systems.

Since then, some schools have worked to improve classroom conditions. Baltimore, for instance, said it has decreased the number of schools without air conditioning from 75 to 14 since 2017.

Columbus City Schools is using hundreds of millions in federal pandemic stimulus dollars to pay for HVAC systems in 16 schools. But six of the 13 schools that were initially planned to be ready by the start of this school year do not yet have working air conditioning.