Other mistake: When the boys cause a mini tremor by blowing up the girls' base, the time at which it occurs is strange because when they do it, both Stan's parents are at home (even though they both have jobs), Ms. Choksondik and Mr. Mackey are at Choksondik's house getting it on (indicating that school is over) and the other teachers are still at the school.
Revealing mistake: Mr. Mackey's glasses do not have the part that goes over his nose unless he is looking sideways, then it suddenly appears. (00:17:40)
Continuity mistake: When Miss Chokesondik first lectures the girls on STD's the words "Sexually Transmitted Diseases" appear on the blackboard although partially obscured as it is a narrow shot of the teacher. The view then changes to a wide shot of the blackboard and nothing is written on it. Miss Chokesondik then proceeds to write "Sexually Transmitted Diseases" on the board. (00:05:35)
Continuity mistake: In the background we see an ambulance with "South Park Hospital" written on it. It is supposed to be called "Hells Pass Hospital." (00:19:55)
Continuity mistake: During the first classroom scene, Token is in the back with Kenny partially in front of him, but when we see the closeup of the projector with Token in front of it, we don't see Kenny anywhere. (00:04:45)
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
Bishop73