Sorry, I have to disagree. The meaning of ****** is a black person, I don't believe you can interpret it any other way. If someone described someone to me as a '******', I would natually assume a dark skinned person. I definitely would not be thinking a "stupid, undesirable, unworthy, disrespectful person".
But I agree with the fact that the statement "The kid interviewed just wants his teacher to be unemployed". Admittedly, I don't live in America, but I assume ****** would be a word used and heard pretty frequently. If one of his school mates had called him a ******, or even some guy he bumped into on the street, would he having a huge cry like he is now? I doubt it.