New York City has dedicated nearly $29 million over the next five years to buy and install air conditioning units in all of its classrooms.
Mayor Bill de Blasio said Tuesday that that "countless parents" have raised the issue at town hall meetings.
Council Member Brad Lander says hot classrooms make it hard for kids and teachers to concentrate. He says some students with asthma or special needs could not attend classes because of the heat - and some kids have even fainted.
About 11,500 classrooms - 26 percent - currently lack air conditioning.
De Blasio's predecessor once made headlines for saying hot classrooms don't excuse students who are taking tests.
"It may be a tiny bit uncomfortable, and these are young, strong people," then-mayor Mike Bloomberg said in 2012 amid a heat wave. "Once their safety, their health is OK, yes, they have to take the test. That's what life is all about."