A new answer comes in the form of a study — out of Vanderbilt University in Nashville, Tenn. — that is as clear as it is controversial.
The focus of the research is Tennessee's Voluntary Pre-K program. It's state-funded preschool on a grand scale, serving 18,000 of the state's poorest children, costing about $86 million a year and built on one big assumption:
That the answer to that earlier question is, "Very."
And Vanderbilt researcher Dale Farran says that at first glance, her team's results showed a big positive impact.
"The children who'd had the Voluntary Pre-K program were much better prepared for kindergarten by all of our achievement measures — significantly so," Farran says.
The Vanderbilt researchers followed nearly 800 children through the program along with a smaller control group of kids, most of whom did not attend pre-K.
Here's where the controversy starts: By the end of kindergarten, Farran noticed something odd in the data: "The children who had not had pre-K caught up," she says. Keep in mind, all of the kids in the study are low-income, which makes the team's next headline even stranger.
"By the end of second grade," Farran says, "the children who'd had state pre-K were underperforming the control children. And that continued into third grade."