Ten-year-old Acadia Boyer of Oxford, Maine, still remembers a particularly hot day in school in detail.
“It got to, like, 100 degrees. I was upstairs, so it was really hot because heat rises, so I just come home being like, 'It's so hot at school,' and I was like sweating and like, not wanting to go to school,” she said.
It was the shoulder season in September 2023. School was back in session at Oxford Elementary, but there was an early fall heatwave that lasted about a week.
“I was exhausted, I was grumpy, out of breath. Friends of mine were going down to the nurse because I felt sick to their stomach, or their or they had headaches,” she said.
Acadia’s mom, Shauna Boyer, attended an open house for parents and recalls being shocked at how warm it was inside the school.
“It was sweltering," Boyer said. "You stood in the room, and I didn't even want to really be there, you know. So I couldn't imagine how it felt for the kids, but also for the staff.”
The next year, Boyer brought new thermostats into the school.
“There are thermostats in the buildings. However, they were maxed out. So we couldn't actually tell how hot they were. They were maxed out at 94 degrees,” she said.
In Maine, a cold-weather state, many of the school buildings are older, and have been built to hold heat in during harsh winters, rather than provide air circulation and cooling.
According to the 2025 Maine School Building Inventory Report, nearly a quarter of schools in Maine lack air conditioning. Only 15% have it in the majority of rooms in the building. If present at all, it's common for AC to be limited to a handful of administrative offices. And 54% have AC in less than a third of the total area of the school.
Many school administrators are aware of the problem, but getting funding to address it is a challenge. Federal grant programs for energy upgrades to school buildings have been canceled or delayed, and there is limited state funding to go around.
Chris Howell, superintendent of the Windham Raymond School District, said the lack of air conditioning hasn't been a huge problem until the past five years or so.
“We actually had a couple days in which we ended up sending students home because the heat index and classroom just got so, so high,” he told Maine Public.
Classrooms on the upper levels of buildings have it particularly bad, according to teachers throughout the state, who say they try to cool rooms down by turning off lights, pulling the curtains and bringing in fans from home.
“You're a teacher, so you just keep going, but I would get really tired, headachy, um, drank a lot of water, but that's still that dehydration factor gets the better of you,” said Sarah Childs, who teaches 3rd grade at Raymond Elementary.
Childs' second-floor classroom has a wall full of windows with a lovely view looking out over Sebago Lake. But for safety reasons, she is only able to open the windows a maximum of four inches — not enough for a box fan or to get the air circulating. She says she can see the effect heat has on her students.
"Their little cheeks will get pink. And you know, we just focus on hydrate, hydrate, hydrate,” she said.
There are no state standards for indoor school temperatures. But studies have shown that students who learn in hot classrooms are more likely to experience fatigue, headaches and difficulty concentrating. They are also more likely to miss school and perform poorly on tests.
As human-caused climate change warms the planet, the number of days over 90 degrees is expected to at least double across parts of Maine by 2050. Studies show people in cold-weather states suffer from heat illnesses at lower temperatures than people in hot-weather states. And children are one of the vulnerable groups at risk from high heat.
After experiencing high school temperatures firsthand, Boyer said she realized what was once unusual heat in Maine was quickly becoming the new normal.
“As I did my research, I realized, this isn't going to go away. I was looking at temperature and how we continue to go up and up and up. This is going to be something that I think Maine is going to start to see a lot more of,” she said.
So she brought the issue to her local representative in Oxford, State Sen. Rick Bennett. He sponsored a bill, LD 11, that requires all school districts throughout the state to set temperature standards.
“It is a recognition of the fact that our temperatures have changed. Our climate has changed," Bennett said. "Particularly in the autumn and the spring, temperatures are often just terribly, terribly warm to be educating kids.
“A lot of our school buildings were built in a different age, and even if a school building was built 15 or 20 years ago, people didn't really think about cooling the buildings because we didn't have the kind of temperature extremes that we have,” he said.
Lawmakers passed the bill; now, all Maine school districts will be tasked with creating temperature standards for their districts, limiting the highs and lows that their classroom thermostats can hit.
“Really ideal learning is usually between 68 and 73 degrees Fahrenheit, and many times, particularly in the shoulder seasons, the temperature in the classroom far exceeds that,” Bennett said.
There are no specific statewide requirements from the Department of Education; nor is there a deadline for schools to adopt the new policy. Bennett called the new law "a first step" and said it was designed to avoid undue hardship for districts that may not be able to afford upgrades right away. The DOE does has guidance stating temperatures must be “a comfortable environment for employees and students.”
Raymond Elementary got a serious update to their HVAC system this past summer — new air source heat pumps. Superintendent Chris Howell says the district has slowly been working on upgrading the energy systems of each of its buildings — and staff tell him it's a noticeable difference.
“One of the things that we've heard from our staff members that are now in climate controlled spaces is that a difference and in just kids attitudes and kids energy and willingness to really step up to the next activity when they're not sitting there sweating all over their desk and, you know, totally flush with heat makes it make big, big, big difference,” said Howell.
When Childs walked in on her first day to the newly climate-controlled building, she says, it felt amazing.
"I'm like, wow, I'm not going to die every day,” she said.
Now, the temperature hovers between 70 and 72 degrees. Hansen can see the temperature in each room of each building in the district from his "mission control" on his two big computer monitors, and make adjustments if needed. The system is more energy efficient, and filters the air, too, he said.
Hansen said, past temperature control, the district investing in newer, greener technologies makes financial sense, too.
"If, you know, we can save $80,000 on utilities and not increase it, that's, that's potentially a position for an ed tech that could be working with a child. If we save $100,000 that's a teacher that we could have working with benefits."
This story was reported as part of a collaboration between Maine Public and the Portland Press Herald.