You can count math studies as up to 5 classes, since that's the number of normal-track classes it covers. Also, having TA'ed graph theory for pikhurko and mack

You can count math studies as up to 5 classes, since that's the number of normal-track classes it covers. Also, having TA'ed graph theory for pikhurko and mackey, and having TA'ed 251 twice, I still see 251 as the hardest.