This is just another example of the racism that we've allegedly 'transcended' in this country. Remember with Obama's candidacy came all the lofty rhetoric about him being a "post-racial" Black candidate? (Saying he's a Black candidate in and of itself contradicts the post-racial crap but that's beside the point.)
This country is STILL polarized and still plagued with bigotry and racism (racism being the result of collective bigotry that dehumanizes another ethnicity & impedes their social, economic & political empowerment). This guy's attitudes have been passed on to his children and the kids in his classroom. Some will reject it but others will embrace it right away and the viciousness will continue.
Imagine being a kid of African descent in that classroom when that was written up on the board. Think about that for a moment. A person in a position of ultimate authority in your life during those long hours at school, day after day, has just let you know in no uncertain terms that even a Harvard educated man (graduated magna cum laude, no less), a constitutional scholar and a presidential nominee of the Democratic party is nothing more than a *racial epithet*.
Think of being a young kid and how desperately you wanted and needed to fit in, to not be someone who is pointed at or considered an aberration from what is considered the norm. Now you've learned that even in 2008, no matter how much education you have or how successful you are in your career, there are people like THAT (in positions of trusted authority) who will see your skin color and reduce you & your achievements down to one single, derogatory word.
If the left doesn't get it together and recognize that there is much to do regarding this issue (on the left side of the political spectrum as well as the right), then they should not act indignant or surprised that clergy like Reverend Jeremiah Wright and Reverend Pfleger have a large and receptive audience.