I've written about the failure of the Head Start program before, but here's more information.
Given that it doesn't show any lasting effects--and what's the point, if it doesn't have any effect--why does that program still exist, $180 billion dollars later? Because it's a liberal government program that has a constituency that votes Democratic. And it makes libs feel like they're doing something to help poor kids.
Reality-based community? This program doesn't even meet its own goals! Why do you continue to support it? Yes, I know the answer, I just want you to admit it.