I don't disagree with the results of the study, but I think the attitudes of younger children to race is changing for the better. One anecdote that happens to me nearly every year in mentoring elementary school boys comes in February when every one reads a Jackie Robinson biography for Black History month.
After I attempt to explain the Negro League, I get asked a version of this question:
"But I don't understand. Why wouldn't you want a good player on your team?"
Kids today simply don't buy-in to the 'because he's black' argument at all. Indeed, they don't get it, whether they are black or white.
Don't know about the asians, they're all too smart to need a mentor.