Former NFL linebacker Aaron Maybin was growing frustrated as he repeatedly vented on social media about shivering Baltimore City schoolchildren enduring unheated classrooms.

"I was tweeting about it and people just weren't getting it," said Maybin, who teaches art at Matthew A. Henson Elementary School, on Monday.

And then it struck him: People need to see it.

So Maybin, 29, set his phone down and hit "record." The Twitter video last week of kids seated in the school library with winter coats — and Maybin clasping his hands together for warmth — went viral and propelled him into the forefront of what's become a prominent educational issue and the political debate over who is to blame.

"When you see something with your own two eyes, then it's harder to ignore it," said Maybin, an artist and poet who tries to use his paintings to teach kids about life. "Until you see it, it's easy to say, 'It might not that be bad.' "

Aided by national publicity generated by the former NFL first-round draft pick, a GoFundMe page launched by Coppin State student Samierra Jones had raised more than $76,000 as of Monday night to purchase space heaters and outerwear "to assist in keeping these students warm." The goal had been $20,000.

"This is an example of how you can use the Internet in a positive way," said D. Watkins, a lecturer at the University of Baltimore and founder of the BMORE Writers Project. "I think he was definitely instrumental in bringing a lot of attention to this."

In the past several days, Maybin has been helping collect contributions of coats, gloves, hats, socks and space heaters from designated collection points around the city.

Anne Fullerton, a spokeswoman for the city school system, said she could not comment on Maybin because he is not a system employee. He is an independent contractor assigned to the school three days a week through an arts program called Leaders of Tomorrow Youth Center.

"I can tell you we are grateful for all the support we are receiving," Fullerton said. "The support is coming from across the country."

She said the system has been working to make sure the donated equipment — such as plug-in space heaters — meet safety specifications.

"It's not just heating where we have problems. There are electrical issues as well," she said.

Mayor Catherine Pugh said hundreds of city and school system employees and contractors worked over the weekend to try to fix broken pipes and non-functioning heating systems. Still, eight schools were closed Monday morning, the last day of one of the longest period of extreme cold weather in decades.

In Annapolis, Gov. Larry Hogan said the state would spend $2.5 million from an emergency, discretionary account to help fix the heat in the schools. He proposed a new "inspector general" to root out what he described as corruption, mismanagement and ineptitude in some Maryland school districts.

Maybin said he is "not a politician," but he does consider himself an activist, and recently completed a book called "Art Activism."

When he heard about the civil unrest in the wake of Freddie Gray's death from injuries sustained in police custody in 2015, his first instinct was to grab his camera and head for the front lines. He ended up documenting those unsettling days through hundreds of photographs posted on Instagram.

His paintings include one of eight clenched fists thrust in the air at the intersection of North and Pennsylvania avenues, where angry residents burned a CVS Pharmacy.

Last week, his initial tweets from the school accused politicians of "finger pointing."

One said: "All the money in the world for building jails. But not enough for basic public school necessities."

"It's really ridiculous the kind of environment we place our children into and expect them to get an education," began another tweet. "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."

He said in an interview that Baltimore is fortunate to have this occur in an election year, and with the General Assembly about to begin its legislative session.

"The people of Baltimore have to make it very clear that we're watching how the elected officials handle this situation," Maybin said.

While artists can be private and introspective, Maybin does not separate his social advocacy from his paintings, said artist Larry Poncho Brown, a longtime mentor.

"Aaron is not doing pretty pictures," Brown said, "he is doing thought-provoking images."

When Brown saw Maybin's school videos — he has posted more than one — "my gut feeling was, 'Aaron go, do what you were placed on this planet to do.'"

Maybin grew up in Baltimore, where his father, Mike, was a longtime official with the city Fire Department.

He excelled in football and was drafted No. 11 overall, out of Penn State, by the Buffalo Bills in 2009. His inconsistent NFL career lasted until 2013.

He said art — and advocacy — had long been his calling.

"This man was an NFL football player. So where is he now? He's teaching in Baltimore city schools," Brown said. "He has always had a vision to help his people and to help other people."

Maybin, bearded and still imposing at 6 feet 4 inches, said he is hardly the first athlete to advance a social cause. But he acknowledges that the public seems to hear more about professional players' misdeeds than good works.

"Nobody typically cares about what an athlete does until they mess up," he said. "For years and years, athletes have had foundations and done programming and raised money."

After the donations came in, Maybin said he was able to tell his elementary-school students a positive story on Monday about how citizen advocacy can be effective. While he cautioned that the heating problems are far from solved, "it was a real-life example of how they can be a part of the change they want to see," he said.

Maybin said conditions at the school had improved since last week. The heat was on, although workers still were trying to raise the temperature inside the gym.

"For the most part we're where we were before winter break, which was not great, but it was okay," he said.