There will be a phased-in reopening instead that will happen by grade levels and happen over the next two weeks.
"The phases will move quickly," Mayor de Blasio said.
On Monday, September 21, 3-K, Pre-K, and early education sites will open including District 75 for special education.
The following Tuesday on September 29, K-5 and K-8 schools will reopen.
Finally, on Thursday, October 1, middle and high schools, secondary schools, transfer/adult schools will reopen.
MORE INFO: NYC Department of Education
Mayor de Blasio said that he has a strong dedication to in-person learning. "There are some out there that suggest that remote education should be our future and I say no it can't be."
The mayor and Schools Chancellor Richard Carranza said that the UFT, the United Federation of Teachers, raised "real concerns" about things that need to be done to start schools safely and effectively. The conversation lasted several hours, according to the mayor.
"I want to thank them for the forthright conversations we had yesterday," said Michael Mulgrew, UFT President. "They said that in order to do this we need to do it right."
"Today's announcement means that all of the planning our schools have done up to this point will continue. And we're giving schools more staff more time and more support this helps us to have the strongest possible start to the most unconventional school year, any of us have ever experienced. And I know that I have 100% confidence that our educators will rise to the occasion," Carranza said.
Mayor de Blasio also announced that the city is adding 2,500 additional educators. Just this past week the city had added 2,000 more for an immediate total of 4,500 additional teachers.
Councilman Mark Treyger, the chair of the City Council's Education Committee, said Thursday's delay of in-person learning was a surprise to him and staff in schools, many of which remain understaffed and unprepared.
"This is a sloppy and rushed attempt at crisis management, and I've argued that all along. The mayor's promise of in-person services was always going to be inadequate. I've been arguing this throughout the summer. And now when the rubber hits the road and Monday was quickly approaching, and schools in my neck of the woods were requesting 90 teachers to meet this hybrid model, I knew it was not going to work," Treyger said.
The news came as teachers continued to voice serious concerns over safety, and now some parents are shaken after a video chat was hijacked in Brooklyn.
A parent of a student who attends IS 259 in Dyker Heights is outraged after she says her daughter's first day of online orientation was hijacked.
The mother tweeted that students began posting pictures of President Donald Trump followed by porn.
The class was eventually taken offline.
The district says despite the fact that this happened, they have strict security settings. They are now investigating.
Meantime, teachers are sounding the alarm and holding protests across the city as students get closer to returning to schools in-person.
Video Thursday morning showed teachers rallying outside Cardozo High School in Bayside, Queens.
They were protesting what they say are unsafe conditions inside the building and lack of adequate staff. This was prior to the mayor's announcement of additional educators.
Teachers there claimed they are short 13 people who would normally cover 65 classes.
They also say they were unable to get into online meetings Wednesday using district-provided technology.
The teachers want to delay in-person learning until they feel it can be done safely. It appears they got as they wished with two additional weeks to prepare.
Teachers in other parts of the city fear their schools aren't ready with enough PPE or nurses, and there are still ventilation concerns.
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