The photo was taken during the Boston busing crisis, a time when liberals decided it would be a good idea to take inner city white kids and bus them across town to black neighborhoods so that they could "integrate" with the black schools. And vice versa, black kids were shipped into white neighborhoods.
Even if you don't know the story, you can guess how it probably turned out. Everybody in the city ended up getting an equally crappy education. Except of course, for the children of the liberals who foisted this upon us. They lived out in the suburbs that were at that time about 99% white and were completely unaffected by forced busing.
Anyway, that one photo turned public opinion against the anti-busing crowed once and for all. Made them all out to be bigots. Not many white folks publicly made a fuss about busing after that and those that could, quietly and rapidly moved out of the city and never returned.
And as we know today from Trayvon and Brown, facts mean little in the face of inflammatory propaganda. Has someone even documented what was actually happening in that photo? Things are seldom what they seem when vicious campaigns of lies get going.