NEW YORK (CBSNewYork/AP) — Nearly 22,000 families applied for seats in the expanded New York City pre-kindergarten program in the first day of the new registration period Monday, Mayor Bill de Blasio’s office announced.

The sign-up period began Monday for registration for pre-K this fall. All 4-year-olds are entitled to a slot in the free program this September.

On Monday alone, a total of 21,938 families applied for spots in the pre-K program, according to the Mayor’s office. That is up from 6,500 applications the first day last year.

The figure broke down to 2,202 applicants in Manhattan, 3,785 in the Bronx, 6,251 in Brooklyn, 7,700 in Queens, and 1,965 on Staten Island.

The initial sign-up period ends April 24.

The expansion of pre-kindergarten is a key component of Mayor Bill de Blasio’s administration. His team expanded the allotment of pre-kindergarten seats to more than 50,000 last fall, and the aim is to increase it to more than 70,000 students this September.

“We’ve made Pre-K for All the centerpiece of our vision for a more fair and equal city. Today is the culmination of a commitment we made to every family that we would open this door of opportunity to every child,” Mayor de Blasio said in a news release. “Come September, more children than ever will walk through the doors of our district schools and Early Education Centers on a path that will help them succeed in their education and beyond. And their families will have peace of mind that there is a free, safe and enriching place for their children to grow and thrive.”

De Blasio originally planned to pay for the program with a tax hike on wealthy New Yorkers.

That proposal failed in Albany. But the mayor’s lobbying led to the state increasing its allocation of funds to pay for the program.

For more information about the program, click here.

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