If you look up the United States' largest school district on the National Center for Education Statistics' database, you won't find the New York City system — the database has split the city's enrollment of more than one million students into smaller geographic districts.

But the New York City Education Department reports that its 2008-09 public school enrollment was 1,029,459, making it by far the largest public school system in the United States.

To relieve crowding and address the continuing need for modern classroom space, the city has added 26 new school sites and 17,000 additional seats for the 2010-11 school year. That makes more than 80,000 new seats in New York City schools since 2003: 19,198 in the Bronx; 18,900 in Brooklyn; 16,900 in Manhattan; 30,233 in Queens; and 4,669 in Staten Island.

"Thanks to strong support from the state and city council, we are in the midst of the largest school construction effort in New York City history," says Mayor Michael Bloomberg.

The largest of the new spaces, with 2,310 seats, is the Mott Haven Educational Campus in the Bronx. It will accommodate several schools — New Explorers High School, Urban Assembly School for Careers in Sports, Bronx Leadership Academy II High School, Knowledge is Power Program (KIPP) Academy Charter School and KIPP NYC College Prep Charter High School.

Another new site is the Metropolitan Avenue Campus in Queens. It has 1,911 seats and will house the Metropolitan Expeditionary Learning School and Queens Metropolitan High School.