The Mamdani administration says more than "500 free universal childcare providers" will be ready for 2-year-olds this fall.
Seats will be available in Manhattan, Queens, Brooklyn and the Bronx. Programs on Staten Island will launch in 2027.
On social media, the mayor thanked participants at the Fort Tryon Park race for showing up.
The applications were made available earlier this week and will remain open through June 26 for families living in School Districts 6, 10, 18, 23 and 27.
The initial communities that will receive 2,000 2-K seats are:
Washington Heights and Inwood
Fordham and Kingsbridge
East Brooklyn: Canarsie, Brownsville, and Ocean Hill
Ozone Park and Rockaways
New York City is home to more than 50,000 2-year-olds, and city leaders say the program will eventually expand to become universal.
Families can apply online through MySchools, by calling 718-935-2009, or by visiting one of the city's Family Welcome Centers.
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