Mayor Bill de Blasio announced Sunday that New York City's public school system will be shut down, the city's most drastic measure yet aimed at containing the spread of COVID-19.

Public schools will close Monday, after what de Blasio described as an "extraordinary painful decision" that had become necessary as the number of cases citywide surged to 329. Schools will close through the end of Spring Break on April 20th, but the mayor said there was a "real possibility" that they may remain shuttered for the year.

"There are so many parents who depend on our schools for meals and for their children," de Blasio said. "I am distraught at having to take this action, but I became convinced over the course of the day there was no other choice."

Remote learning will begin March 23rd, a system that has never before been attempted on this scale, he said. The city's public school system is the largest in the nation, serving 1.1 million students. First responders, healthcare and transit workers, and the city's "most vulnerable populations" will receive childcare at "regional enrichment centers" beginning March 23rd. Teachers will be trained over the next few days, and schools will be open for grab-and-go meals only. Breakfast and lunch will be available until April 8th, before the previously slated spring vacation.

Teachers and principals will be required to come into school Tuesday, Wednesday, and Thursday for guidance and training on remote learning, Schools Chancellor Richard Carranza said during the press conference. He encouraged parents to sign up for a New York City schools account.

Carranza said the distance learning will not mirror schools, adding that doing so is "impossible."

Guidelines for the Department of Education's "Learn at Home" resources for pre-kindergarten through 12th grade were available online in English as of Sunday. The materials included daily study schedules, instructional activities, as well as educational television shows, listed by grade-level.

"These materials do not replace what your child has been learning at school, but during this unusual time it is important that students continue to read, write, do social studies and science activities, and work on math problems," the website for the new materials reads.

The closures come after a growing push for de Blasio to shutter schools from elected officials, parents, the United Federation of Teachers, the powerful health care workers union, 1199 SEIU, and 12 members of congress led by Representative Jerry Nadler.

As of Sunday morning, the mayor was still resisting calls to shut down the system, pointing to the challenges faced by families who depend on schools for childcare and meals.

"I know there are millions of parents that rely on our public schools," de Blasio said on WBLS Sunday morning. "The kids, not only do they need an education, they need a place with meals. They need adult supervision."

Demands to close the schools intensified throughout Sunday. Hours before the announce, Governor Andrew Cuomo gave the mayor a 24-hour deadline to come up with a plan, after Nassau, Suffolk, and Westchester counties announced a two-week closure.

NYC must have a plan in place in the next 24 hours for childcare for essential workers and a plan to make sure kids will continue to get the meals they need.



NYC schools will close early this week.



This action is necessary to reduce density and mitigate the spread of #COVID19. — Andrew Cuomo (@NYGovCuomo) March 15, 2020

"This action is necessary to reduce density and mitigate the spread of #COVID19," Cuomo said in a tweet. He said a childcare and meals plan was critical to set before systems formally closed—especially for healthcare workers and first-responders with young children.

Ahead of the announcement, hundreds of teachers had planned to stage a "sickout" on Monday in protest of mayor's reluctance to close schools. Some 400 organizers were on a call about the protest on Saturday, led by MORE: The Movement of Rank and File Teachers, a faction of the union.

The United Federation of Teachers president Michael Mulgrew has called on the Department of Education to maintain services for vulnerable students. Some local lawmakers have suggested a "summer school model."

Up to 21 states, serving roughly 26 million students, have already closed across the country, according to the American Federation of Teachers President Randi Weingarten.

"What is it that they know that Mayor de Blasio does not?" she said at a press briefing with UFT to demand de Blasio close schools Sunday afternoon.

Some health experts backed the mayor's initial hesitance. Jennifer Nuzzo, an epidemiologist and professor at Johns Hopkins Bloomberg School of Public Health told the Times she was wary of school closures without a proper plan. "I don't really understand what the endgame here is," she said, adding that it was "largely an experiment.

Aaron Benoit, a Brooklyn high school English teacher, said that schools remain in "uncharted territory" in terms of how the city and state will make up for the safety net schools provide students.

"I think what’s overdue is a real sense of direction on this," Benoit told Gothamist on Sunday. "Obviously we’re not trained in these kind of emergency situations, but I feel like most people who get into teaching believe in the common good.

"It never needed to be as antagonistic as I feel it got with the mayor on one side and everyone else on the other," he added.

Other teachers were already seeing the effects as COVID-19 spread through their own schools, requiring some to be closed for a 24-hour deep cleaning period. P.S. 306 in Queens was undergoing cleaning on Sunday after a confirmed coronavirus case, a day after a Staten Island school also had a confirmed case.

With Jake Offenhartz.