Preschool’s ‘Sleeper’ Effect on Later Life
Does preschool help children become more successful adults? Twenty-five years ago, I thought that there wouldn’t be a straightforward answer to this question—development is just too complicated and hard to study. I was completely wrong. A clever and compelling study by the economists Guthrie Gray-Lobe, Parag Pathak and Christopher Walters has just appeared as a National Bureau of Economic Research working paper, and the answer is clearly “yes.” But the results also raise fascinating questions about how early experience influences later life.
In defense of my earlier view, development is, in fact, complicated and hard to study. How can we tell that there aren’t other differences between children who go to preschool and those who don’t? There are so many different kinds of preschool programs, so many different measures of success and so many other things that happen to children as they grow up. Wouldn’t early effects just wash out later on?
Some of these problems have been reflected in policy debates. Early studies of big public programs, particularly Head Start, found that children’s grades and test scores improved at first, but the effects faded out in elementary school. On the other hand, some more controlled and longer-term studies found that children who attended preschool were healthier and wealthier many years later. But these studies looked at experimental, relatively small interventions, like the Perry Preschool Program in Ypsilanti, Mich.
