Mr. de Blasio said his new initiative would build off the success of his universal prekindergarten program for 4-year-olds, which has enrolled almost 70,000 children. He also said it would require hiring 4,500 more teachers, leaving Mr. Matison worried that he could lose even more staff members.
“It is really a frightening prospect,” he said.
In the weeks since the mayor revealed his proposal, questions about whether the new program can succeed have been raised by preschool providers, state legislators and critics who say he is setting a lofty and politically popular goal that he has no realistic plan to achieve.
In addition to hiring staff, the expansion to 3-year-olds would require hundreds of classrooms, including some in the most crowded — and expensive — parts of the city.
Most critical, to actually make the program universal, Mr. de Blasio needs to secure $700 million in state and federal funding. On its own, the administration has said, the city can fund the program in only eight of its 32 school districts. It is starting with a pilot program this fall in just two districts, in the South Bronx and the Brownsville neighborhood in Brooklyn.
Some state legislators have said that they are not prepared to pay for preschool for 3-year-olds in New York City until there is free prekindergarten for all 4-year-olds in the rest of the state. Currently, according to the State Education Department, roughly a third of New York’s 4-year-olds do not have access to public prekindergarten.
“I respect the mayor and his plan, but I would say that we have a lot of work to do statewide first,” State Assemblyman Kenneth P. Zebrowski, a Democrat from Rockland County, said in an interview. He noted that Rockland County had enough prekindergarten seats to serve only about half of its 4-year-olds.
Freddi Goldstein, a spokeswoman for Mr. de Blasio, said that while there were hurdles, “The science is clear that the earlier we reach our youngest children, the better chance they have to succeed later in life.”
She added that there were “still important program development discussions to be had, but the mayor refuses to wait.”
New York City’s publicly financed early education system is complex and fragmented. Mr. de Blasio’s universal prekindergarten program is free and serves all 4-year-olds, regardless of family income, in schools and community-based organizations. These programs run six hours and 20 minutes daily and operate only when school is in session.
Then there are early education centers that specifically serve low-income families through the city’s…