I'd suggest reading this article: http://www.slate.com/id/2178122/entry/2178123/ http://www.slate.com/id/2178122/entry/2178123/ "white kids from households wi

I'd suggest reading this article: http://www.slate.com/id/2178122/entry/2178123/ http://www.slate.com/id/2178122/entry/2178123/ "white kids from households with annual incomes of $20,000 to $30,000 easily outscore black kids from households with annual incomes of $80,000 to $100,000." In an adoption study where black and white babies were both adopted by high IQ white parents, there was a one standard deviation difference ( 15 IQ points) between the black and white children.