NEW YORK CITY (NewsNation Now) — New York City Mayor Bill de Blasio announced Sunday that the city’s public school system, the largest in the U.S., would begin phased reopening of schools starting in December.

The schools were closed less than two weeks ago after the citywide rate of coronavirus tests coming back positive exceeded a 3% benchmark agreed to by the mayor and teachers’ union. De Blasio said the 3% benchmark was being scrapped/

“It’s a new approach because we have so much proof now of how safe schools can be,” de Blasio told reporters.

Pre-kindergarten classes will reopen Dec. 7 for students whose parents agree to a weekly testing regimen for the virus. Schools that serve children with special educational needs, known as District 75 schools, will reopen Dec. 10. De Blasio said middle schools and high schools would reopen at later dates that had not yet been set.

Schools Chancellor Richard Carranza, who joined the mayor at a news conference, said with the new measures he believed the city could “safely and successfully keep our schools open for the duration of this pandemic.”

The city has more than 1 million public school students. As of the end of October, only about 25% of students had gone to class in school this fall, far fewer than officials had expected.

New York City’s school system, like others across the nation, halted in-person learning in mid-March as the virus spiked.

While many big U.S. school districts later decided to start the fall term with online learning, de Blasio pushed for opening schoolhouse doors.

The reopening date, originally set for Sept. 10, was postponed twice as teachers, principals and some parents said safety precautions and staffing were inadequate, with the teachers’ union at one point threatening to strike.

The city agreed to changes, including hiring thousands more teachers and testing 10% to 20% of all students and staffers per month for the virus.

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