One might draw from this that there are cultures which thrive in an educational environment, and those that don't.
While some might try to tie results to race, it appears that race plays a smaller part than cultural factors.
I think it shows race and education to be the same. It shows whites/asians doing about 200 pts. better than blacks of the same educational level and it shows kids of graduate school parents doing about 200 pts. better than kids of the same race but less than HS parents.