NEW YORK -- First day back-to-school jitters were met with boiling temperatures.
More than 900,000 kids returned to New York City public schools Thursday, just as the city recorded its first heat wave of the season.
At the Highbridge Green School on West 167th Street, students said half the classes had air conditioning and half did not, and that's not the only challenge that was encountered citywide.
"I had art class, and in there was really hot, so we had to use tiny fans to cool the room down," sixth grader Eunice Marmol said.
Marmol was exhausted from her first day. Her new school didn't have a fully functioning air conditioning system.
CBS New York's Lisa Rozner asked Marmol if she could concentrate.
"Kind of, but it was like at certain moments it was getting too hot. So I had to go out to get water and stuff," Marmol said.
Watch: Schools Chancellor Banks in studio
Rozner was shown a photo of a portable AC unit put inside some of the classrooms. It's not clear how many classes citywide had the same issue, but the president of the teachers union said the city was not prepared for the excessive heat.
"I am not happy that New York City has not completed its School's Cool program, which was the money appropriated by the City Council over 10 years ago that said every classroom in New York City would be air conditioned. It's not," United Federation of Teachers President Michael Mulgrew said. "Shame on every administration that has not fulfilled its promise.
Watch: NYC schools welcome students back
The Department of Education told CBS New York, in part "we are in constant dialogue with New York City Emergency Management and the National Weather Service to ensure effective application of the latest weather updates and conditions."
The first day of school also comes as theis looming. But, even Thursday, parent Evan Brown said a bus never came to East Elmhurst to pick up his 14-year-old son with special needs.
"There was a matron who was connecting with us who was telling us there was no driver, and she was just waiting in the yard," Brown said. "Ended up driving him through traffic to his drop off point, and we ended up getting him there on time.
Watch: Banks extended one-on-one
"Was it hot in the school or no?" Rozner asked 4-year-old Isabelle Adams outside of PS 166 The Henry Gradstein School in Astoria.
"It was cold," Adams said.
"It was really cold," student Delilah Hernandez said.
Students there told Rozner the AC was working almost too well.
"I knew it was going to be cold in there. I packed a sweater because I figured the air conditioner would be bumping," parent Kathryn Adams said.
meant no playing outside.
"Very sad first day," 8-year-old Luke O'Sullivan said. "I couldn't see my friends because they're in different classes."
"We just spent the recess period eating lunch," student Mila Hernandez said. "I really wanted to go outside... because I have friends from a different class. I'm in the gifted program so, yeah."
Because of the extreme heat, the city limited any school-related outdoor activities until 6 p.m.
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