The mayor and Schools Chancellor Meisha Porter were at a Brooklyn school to announce the expansion of the pre-school program to the remaining 16 community school districts, planned for the 2021-22 school year.
The program currently serves about 23,500 students and will expand to an additional 16,500 youngsters.
"3K has been invaluable for so many kids and working families across our city," Mayor Bill de Blasio said. "Now, as we build a recovery for all of us, we are bringing 3K to every district across our city, giving more kids the quality head start they need to grow and thrive."
The announced coincided with the launch of the new opt-in period for parents of preschool and elementary students, offering an opportunity the city initially told parents they would not have, to once again opt their children in to in-person learning.
The period lasts for the next two weeks, ending on April 7, and comes after the CDC released new guidelines that students can be socially distanced in the classroom by 3 feet rather than 6 feet, providing more room for in-person learning.
RELATED: More NYC students can opt into in-person learning, de Blasio says
The United Federation of Teachers said it is still unpacking the new guidance, while the American Federation of Teachers says this new strategy will require more testing, ventilation and cleaning.
"Our concern is that the cited studies do not identify the baseline mitigation strategies needed to support 3 feet of physical distancing," AFT President Randi Weingarten said. "Moreover, they were not conducted in our nation's highest-density and least-resourced schools, which have poor ventilation, crowding and other structural challenges."
Mayor Bill de Blasio, however, remains enthusiastic.
"Now we have the CDC saying even further, we can bring back more kids to our schools," he said. "And in fact, what our healthcare leaders always say...that's in the interest of the health of our children and our families - mental health, physical health - to get them back into school."
The mayor has also announced city workers will start returning to their offices on May 3, with mask wearing mandatory.
He made that announcement after critiquing Governor Andrew Cuomo for reopening businesses like fitness classes too quickly.
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