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SALT LAKE CITY — The new school year's about to ramp up and it's likely parents are running through a mental checklist to make sure that everything's in order: Do we have all the school supplies we need? Is the paperwork done?
Will the classroom be too hot?
That latter question is among the most important for learning and student well-being as high temperatures continue to rage in much of the country and school air conditioners — if a school has a working air conditioner at all — struggle to keep up.
Temperature control in classrooms is not just about perceived comfort. It's vital to both learning and health. In 2018, Harvard Kennedy School published a working paper that offered "the first evidence that cumulative heat exposure inhibits cognitive skill development and that school air conditioning can mitigate this effect." Put simply, brains that are fried by hot classrooms don't learn the way they should.
And a lot of classrooms are going to be too hot. In June 2020, the Government Accountability Office estimated that more than 4 in 10 public schools districts need to update or replace the air conditioning systems in at least half of their schools, which counts out to about 36,000 schools across the country.
In 2021, the EdWeek Research Center conducted a nationally representative survey of schools and learned that somewhere between one-third and one-half of U.S. schools lack adequate air conditioning. The report said nearly half the educators called heating and cooling problems "an urgent issue" in their school district.
NEA Today, the publication of the National Education Association, summarized what's been a growing problem this way: "As heat waves — and wildfires! — become more frequent, many schools are still ill-equipped to deal with the effects of extreme heat and poor air quality on students and educators."
At Adelaide Elementary in Federal Way, Washington, office staff found themselves dealing with a heat wave in May 2023 because the school didn't have a school nurse on duty. Office manager Sara Rowe said they dealt with students who were fainting in the heat, some with bloody noses, others with headaches and many with growing anxiety. They finally called parents to come get their children. "I'm not a trained health professional, so it was very difficult dealing with these problems," Rowe said. "And because of security concerns, we're not allowed to keep windows and doors open. There was no way to get that airflow."
How hot classrooms hurt kids, teachers
The Harvard paper, which cited data from 10 million PSAT test takers, found that "hotter school days in the year prior to the test reduce learning, with extreme heat being particularly damaging and larger effects for low-income and minority students. Weekend and summer heat has little impact and the effect is not explained by pollution or local economic shocks, suggesting heat directly reduces the productivity of learning inputs." Additionally, they found that air conditioning in the school "almost entirely offsets these effects." Without air conditioning for hot classrooms, every 1-degree increase in temperature translated to a 1% reduction in learning, the researchers reported.
The ideal temperature for a classroom to maximize students' ability to learn reading and math is 68 to 74 degrees Fahrenheit, according to Pennsylvania State University. When its Center for Evaluation and Education Policy Analysis looked at school facilities themselves and how they contribute to both learning and student well-being, getting the temperature right proved to be important.
"One consistent research finding across individuals of all ages is that the temperature in which a person works affects engagement levels and overall productivity — including student achievement. Anyone that has worked in a classroom or office that is too hot or too cold knows how difficult it can be when trying to work when the temperature is uncomfortable. According to the best analyses, the ideal temperature range for effective learning in reading and mathematics is between 68 degrees and 74 degrees," the analysis found.
As Education Week reported, "Experts agree that classrooms would ideally be kept at a temperature that doesn't require fans, space heaters or winter wear to make students and staff more comfortable." The report cited a study where 10- to 12-year-old children in two classrooms were tested, finding that when the temperature was reduced from 77 to 68 degrees Fahrenheit, their performance on two numerical and two language-based tests improved significantly.
Too hot to learn — or feel — well
A 2020 study in the journal Nature Human Behavior said that "students who experience hotter temperatures during the school year before their exams exhibit reduced learning" and the scores drop for every day they experience temperatures close to or above 80 degrees. The impact is largest in lower-income school districts.
NBC News reported that in Florida's Polk County, the teacher's union filed a class-action grievance against the school district because of classroom temperatures.
A California report entitled "Hot Weather Standards in the School Setting" that was updated a decade ago noted standards for workers and in child care settings, but nothing to protect children from extreme heat in classrooms. Educators and parents wanted at least the protections offered in licensed day care facilities.
