"It's hard to stay focused because it's so hot in there," one student said.
PHILADELPHIA (WPVI) -- A total of 100 schools in Philadelphia dismissed early on Tuesday, and the district said they will dismiss early again on Wednesday.
Officials with the School District of Philadelphia say the schools do not have sufficient cooling systems.
All after-school and sports activities at the impacted schools are also canceled.
"A lot of the classrooms are like, really hot," said student Savannah Mapp- Evans.
"Some classrooms have air conditioning but most of them don't, so it's hard to stay focused because it's so hot in there," she continued.
Her mother, Brandi Mapp-Evans, said, "When I found out that they had to come back August 29, I was like, 'we might run into the same situation we've had in previous years where it's going to be too hot, they're going to have to send the kids early.' And that's exactly where we are."
Emails and robocalls went out to families.
The school district wrote, "Please know that these decisions, which we do not make lightly, are always made with the safety of our students and staff as our top priority."
Families worked to make other arrangements.
"I work from home. I work per diem," said William Carter, who was picking up his granddaughter from Amy Northwest Middle School. "I'm not making an money sitting here talking to you."
Carter said the heat was predictable and wanted the district to plan better.
Officials told Action News that the district did install 500 air conditioners at 43 different schools over the last year. But still, many schools don't have sufficient cooling systems to keep up with the heat.
Teachers union president Jerry Jordan wrote, "...we cannot and will not rest until every school community has what they need to thrive. And YES, that means air conditioning for every building."
"I think the school district has struggled for funding for years, even when I was a school district student, so they need to just put some money into our schools for these young people," added Brandi Mapp-Evans.
All other schools and administrative offices will continue to operate on a normal schedule.
"We realize that early dismissals, especially those made the day before, can present challenges for many families. Please know that these decisions, which we do not make lightly, are always made with the safety of our students and staff as our top priority," the district said in a statement on Monday.
CLICK HERE for a full list of schools dismissing early August 30 and 31.