When heat and humidity spike, students say it can get uncomfortable inside Winnipeg high school Tec Voc.

"It's just like sweltering hot," said Grade 12 student Caesy Tumambing. "Everyone's sweating. And it doesn’t smell good."

Fellow Grade 12 student Brendan Molinski agreed, "It's really hard to sit and focus on your exam when you’re really hot."

That's exactly what a new study concluded. Conducted by Harvard and other U.S. universities, it found that temperature can directly impact a student’s performance.

Researchers followed 10 million high school students over a 13-year period. They found heat made it harder to study while in school and to concentrate on homework after school.

Pediatrician Dr. Stan Lipnowski, who was not a part of the study, is not surprised by its findings.

"Kids need to be at their best to learn," said Dr. Stan Lipnowski. "And whether they're hungry, sleep deprived, or dehydrated, they're not going to function well."

The researchers looked at PSAT's and found scores started to fall as it got hotter. To fix the problem, the study's authors suggest greater access to air conditioning.

"For Winnipeg School Division, we have over 350 pieces of air conditioning equipment," said Radean Carter. Those pieces are spread across the 78 schools in the division. Each unit has to be inspected, repaired if necessary, and then turned on.

It’s a huge process that takes the entire month of May to complete.

"There are a few schools that when they did their inspections, they discovered they were low on coolant, or they had repairs that had to be done," said Carter. "So those may be taking a little longer."

The division says there are strategies to beat the heat. People can wear loose clothing, eat lighter meals and drink plenty of water.

The study was released by the the National Bureau of Economic Research, a non-profit economic research organization in the U.S.

The working paper notes it has not been peer reviewed.