District officials say installing A/C is not in their budget, especially for the four schools soon-to-be closing, like Irving Primary.
The nearly 430 students still go without cool air in their classrooms, and even take their recess and P.E. classes outdoors.
"We make sure that kids stay hydrated, so we're out at the drinking fountains quite a bit," said Michael Barber, Irving Primary School Principal. "We have fans throughout classrooms that circulate the air to help with the coolness, and we also have an air-conditioned library, and teachers rotate out of the library every 45 minutes, so you kind of get a break from the heat."
According to the local American Red Cross, the faculty are taking the right steps to prevent heat-related illness, but if you are spending time outside, you need to be aware of how you're feeling.
"Know the signs of heat exhaustion," said Erin Miller, the Communications Coordinator for the American Red Cross Central Illinois Chapter.
"It starts out with heat cramps, but if it progresses to the next stage, it's nausea, weakness, definitely go inside. But, if it goes to the final stage which is a rapid pulse, losing consciousness, that's when you need to call 911."
For a full list of heat safety tips, click here.
District 150's last day of school is this Friday, but it's the next couple days that both staff and students need to watch as heat indices reach dangerous levels.
About half of District 150's schools have been coping without air conditioning.