Like many young parents, John and Janine Morreale were willing to stretch their finances to get their child, three-year-old Johnny, into preschool. Both worked full time--John in maintenance, Janine as a teacher--but their joint income was not enough to foot the $6,000 bill, equal to the yearly rent of their apartment. "We were living paycheck to paycheck, and we even had to start borrowing from my mother-in-law," recalls Janine. "It just didn't make any sense."
It makes a lot of sense now. In September, Johnny, now four, started pre-kindergarten at Brooklyn's P.S. 200, the local public elementary school--free. He is one...