Do you know what a challenge you're in for if you're trying to teach dumb asses not to be dumb?
I get what you're saying, and generally speaking white people (especially in America) very rarely, if ever have to deal with oppression or discrimination as blacks and other minority groups do. So yes, when a show portrays a black person as uneducated and / or ghetto, there is a chance that some 'dumb ass' will see it and accept it.... but who cares? There are plenty of people who are capable of rational thought that realize that blacks aren't all born with spears in hand. You'll be a lot better off when you stop worrying about what people in general, and especially dumb asses think.