I doubt you could change parental behavior so would rather put funds into something along the lines of HeadStart, although I am surprised that any gains disappear by 3rd grade...both surprising and depressing.

In our area there is a ongoing effort to re-integrate the largest school district as there is a concentration of poverty. The kids that are from families with funds will simply move so I do not think this will have any overall positive impact. What is interesting is primarily it is a conversation about blacks/whites whereas if you go to any advanced academic competition Asians comprise 90%+ despite only comprising 5-6% of the population in the schools.