Whatís so great about preschool?

Perhaps you’ve seen that ad that shows a kid growing up, making all the right life choices. Drugs? No thanks. Drop out of school? No way! Then, at the end, we learn that this well-adjusted member of society has preschool to thank for his well-adjustedness. The real story might be quite different:

…early education does increase reading and mathematics skills at school entry, but it also boosts children’s classroom behavioral problems and reduces their self-control. Further, for most children the positive effects of pre-kindergarten on skills largely dissipate by the spring of first grade, although the negative behavioral effects continue.

That’s from a new NBER study. (Via Tyler Cowen).