Although this episode claims that Michael attended The Milford Academy, implied to be an all-boys high school, in Top Banana (2003) Michael and Lindsay were supposed to have attended the same high school, at which Lindsay won "Best Hair" and Michael won "Most Likely to Succeed."
In the Klimpy's scene when Lucille is saying to Lindsay "Oh please, everything I've said about you..." there are 2 African American men seated at the table next to Lucille and Lindsay. Moments later, as Lucille is uttering the line "Sorry Lindsay, there goes your dessert" one of the two men is white.
When Jessie first addresses Buster to tell him that he makes people "uneasy", one can clearly see David Cross lower his head as he stifles a laugh. He has to hold back again as the publicist is giving Buster direction with what to do.
When Michael and his son are waiting to be interviewed at the school and Michael says "....and that's the most important thing to me, okay?", you can see that his mouth movements doesn't match what he's saying.