The entire test could be written in Ebonics and deal entirely with ghetto scenarios. The results would be the same. Asians and Whites would do best.
I agree - once again, I attribute it to family structure and sense of responsibility rather than "they're just too dumb". When I was in school in the '50s and '60s, we had a fair number of Blacks in school and they all did just fine. Then, Johnson's "great society" took effect and destroyed them - just as he intended.