One of the big problems is that in the US school districts are highly local, so economically depressed neighborhoods have far fewer resources to educate children. The US really needs state-wide or metropolitan-wide public school systems that assign students by lottery (assuming that good schools are over-enrolled). This will do a lot to level the playing field, however it's far unlikely to happen for reasons of both class and race.

So that leaves universities to level the playing field. If the US ever gets the K12 education system overhauled maybe can argue against this interventionism from universities, but otherwise how do we start fixing today's problems today?