Baltimore closed its public schools on Thursday after former NFL linebacker turned teacher, Aaron Maybin, revealed how his students tried to learn in 40F classrooms wearing coats as icicles formed on the building's rafters.

As temperatures plunged across the Northeast ahead of the powerful nor'easter that moved up the east coast, teachers expressed their outrage at Baltimore students being forced to attend schools with no heat, including Maybin.

'This is what #Baltimore students trying to learn in a 40 degree classroom looks like. Just in case anyone gives a damn...' Maybin wrote in the caption of a video he shared on Instagram.

Parents and other residents in the community also wondered why the students were made to sit inside their classrooms in close to freezing temperatures.

Baltimore closed its public schools when temperatures inside classrooms dropped to 40F on Thursday, forcing students to wear hats, gloves and coats just to stay warm

As temperatures plunged along the Northeast ahead of the powerful nor'easter that moved up the east coast, teachers expressed their outrage of Baltimore students being forced to attend schools with no heat. Former NFL linebacker, Aaron Maybin, is pictured with his students

The Baltimore native, who currently teaches in the city, told CNN that his first-aid kit thermometer showed it was 40 degrees in his classroom Wednesday at Matthew A. Henson Elementary School.

Maybin's Instagram video shows the children gathered around him wearing coats as he shows them how to keep themselves warm.

'Another thing you can do to keep yourself warm is rub your hands together,' Maybin says as he demonstrates.

'That friction keeps it warm and then blow in your hands,' he added.

Maybin, who was drafted by the Buffalo Bills in 2009, is then seen reading a book of poetry to the students who were very eager to learn despite the temperature.

'My students were freezing,' Maybin told CNN Thursday. 'Most were wearing coats, but some don't have them.'

Maybin, who also played for the New York Jets before his career ended in 2013, also said the lights inside the school were off at one point.

Chasity Spears, a parent of one of the students, told WJZ that the classrooms are 'unbearable'.

'There's icicles in the classroom,' Spears added.

'This is what #Baltimore students trying to learn in a 40 degree classroom looks like. Just in case anyone gives a damn...' Maybin wrote in the caption of a video he shared on Instagram

The Baltimore native, who currently teaches in the city, told CNN that his first-aid kit thermometer showed it was 40 degrees in his classroom Wednesday at Matthew A. Henson Elementary School

'My students were freezing,' Maybin (pictured in August 2012) said. 'Most were wearing coats, but some don't have them.' Maybin also said that the lights inside the school were off at one point

Other photos of the students quickly spread across the internet showing the children bundled up inside their classrooms where heating systems weren't functioning properly.

The school system closed four schools and dismissed students early at two others Wednesday, and closed all schools Thursday.

Thursday's systemwide closures came only after parents and a teachers' union expressed their outrage over Wednesday's heating issues.

Dr. Sonja Brookins Santelises, the CEO of Baltimore City Schools, said in a Facebook Live video that part of the problem for the temperature in the schools was due to 'unprecedented frigid temperatures two weeks solid'.

Santelises said the type of weather the area is experiencing has not happened in more than 10 years.

She said that the temperatures combined with the 'very old conditions of our buildings' has proved to be 'quite challenging' for the school system to handle.

Santelises noted that some of the schools have experienced parts of boilers to break and pipes have bursted in others due to the cold conditions.

According to Santelises, about 60 schools reported heating issues during the school day on Wednesday.

Maybin also said that the lights inside the school were off at one point

Dr. Sonja Brookins Santelises, the CEO of Baltimore City Schools, said in a Facebook Live video that part of the problem for the temperature in the schools was due to 'unprecedented frigid temperatures two weeks solid'. Students are seen attempting to learn in 40F temperatures

Maintenance teams resolved many of those issues during that day, Santelises said.

'Nobody in this city, including me, wants folks sitting around in coats and mittens all day,' Santelises said.

Mayor Catherine Pugh said in a statement that she is 'deeply distressed by the substandard conditions that are preventing our children from being where they need to be - in the classroom'.

Pugh said she is 'urging an expedited process to deal with these issues, get these conditions fixed and get students back to school'.

In the meantime, Pugh said the city's recreation centers will be open from 10am-9pm to accommodate the students and the Food Bank and City of Baltimore 'will be providing snacks and food' to the youth who went to the recreation centers.

As maintenance crews worked to fix the heat, a GoFundMe account was established to help the city's schools.

'This fund raiser will help in purchasing space heaters and outerwear to assist in keeping these students warm,' the account read.

As of Thursday evening, the GoFundMe had raised more than $33,000.

Maryland was hit by the powerful nor'easter early Thursday as it moved up the east coast, bringing snow, ice, strong winds and rough surf with it.

Gov Larry Hogan on Wednesday signed an executive order declaring a state of emergency in Somerset, Wicomico and Worcester Counties in anticipation of the snowfall.

According to Santelises, about 60 schools reported heating issues during the school day on Wednesday. Maintenance teams resolved many of those issues during that day, Santelises said. Pictured is the Matthew A Hendson Elementary School where the incident occurred

The Baltimore Teachers Union also issued this letter to Dr Santelises on behalf of the teachers and the students

'I urge all Lower Shore residents – and all Marylanders – to stay warm, stay safe, and avoid unnecessary travel. Freezing temperatures and heavy winds mean increased danger on our roads, even after the snow has stopped falling,' Gov Hogan said on Wednesday.

'The state stands ready to offer any and all necessary resources to impacted counties.'

By 8am Thursday, Maryland State Police said they had already responded to 51 vehicle crashes and 55 disabled vehicle calls.

Heavy snow was expected, between 6 and 8 inches of accumulation, according to the National Weather Service.

Meteorologists reported as much as a couple of inches around Baltimore and 10 inches on the Eastern Shore.

A wind chill advisory will go into affect across Central Maryland at 10pm, lasting through midday Friday.

It is expected to feel as cold as 15 degrees below zero, and as warm as 5 degrees above zero.

Meteorologists warned that such cold can cause frostbite in as little as 30 minutes if skin is left exposed.