Public schools in Baltimore were closed Thursday after the Baltimore Teachers Union demanded they be shuttered until officials can properly assess and fix heating problems that came to a head this week amid consecutive days of freezing weather.

“Kids can’t learn and teachers can’t teach in freezing classrooms and in schools with no heat, frozen pipes and frigid winds coming in through drafty windows,” American Federation of Teachers President Randi Weingarten said in a statement backing the local union’s call for closures. “These conditions are unsafe, unbearable and unacceptable for students, educators and school employees.”

Officials closed four schools Wednesday and dismissed students early at others due to heating issues. Complaints, however, rolled in from more than 60 schools – approximately one-third of all city schools – according to school system CEO Sonja Santelises.

Images of students wearing winter clothing indoors also sparked outrage on social media, and Samierra Jones – a senior at Coppin State University and a graduate of Baltimore City schools – helped spearhead a fundraising effort through the crowdsourcing website GoFundMe aimed at raising $20,000 to purchase around 600 space heaters for the schools and clothing for students.

“Baltimore City Public Schools are currently operating with an inadequate heating system,” Jones wrote. “Students are still required to attend classes that are freezing and expected [to] wear their coats to assist in keeping them warm. How can you teach a child in these conditions?”

As of Thursday afternoon, nearly $27,000 had been raised.

The woes are not new to Baltimore schools, where decades-old facilities have been a constant sore spot during budget negotiations.

As the Baltimore Sun reported, Maryland Gov. Larry Hogan, a Republican, pushed the Board of Public Works to temporarily withhold school construction money until the city’s school district came up with plans to install air conditioning in its facilities. The money was restored last year amid a warning from Santelises that the air-conditioning work may come at the expense of fire safety and roof repair projects, according to the Sun. Meanwhile, several heating and window replacement projects were not recently funded.

“There is substantial deferred maintenance that happens each year with [Baltimore] City Schools because there’s not enough money,” DeRay McKesson, a civil rights and Black Lives Matter activist who grew up in Baltimore and formerly worked as the school system’s chief human capital officer, said on Twitter.

“Projects that aren’t dire … get delayed until later,” he said. “Then later comes [and] it’s a crisis. But it stems from there literally just not being adequate funding.”

The Hogan administration has pushed back against the charge that city schools aren’t funded adequately.

“Our Administration has fully funded Baltimore City Schools for the entirety of our time in office,” Lt. Gov. Boyd Rutherford tweeted. “In fact, we provided more than the formulas called for. The money is not reaching the classroom – ask [school headquarters on] North Ave. why?”

The heating crisis has fueled a larger conversation about the quality of education afforded to historically disadvantaged students – namely, students of color and low-income students.

“It’s really ridiculous the kind of environment we place our children into and expect them to get an education,” former NFL linebacker Aaron Maybin, who now works as a teacher at Baltimore’s Matthew A. Henson Elementary School, wrote on Twitter. “I got two classes in one room, kids are freezing, Lights are off. No computers. We’re doing our best but our kids don’t deserve this.”

Maybin posted a video of himself talking to students about heating issues as they sat in front of him in winter clothing.

Closing schools has always been a difficult decision for districts that serve lots of poor students. Parents often cannot afford to take a day off from work to watch their children, and many students also depend on schools for breakfast, lunch and sometimes even dinner.

Those are some of the pressures that once led Carmen Fariña, the head of New York City’s school system who recently announced her retirement, to keep schools open in 2014 despite a winter storm hitting the city – a decision for which she was widely criticized.

It’s unclear how much longer Baltimore officials will keep city schools shuttered, as Santelises grapples with some of the same issues.