The assorted finds of Artefact Publishing
It appears that television shows that have a school as part of their setting have an aversion to “good” teachers. If ever a new or previously unseen teacher comes to the fore as an inspirational, entertaining, wonderful figure, he (it’s always a he) is actually a bad person and will be discredited and shooed off in short order. My personal theory about this is that:
Of course, as far as I can remember I am basing this entirely off an episode of My So-called Life and an epidoe of Veronica Mars, but I would be not at all surprised to find it elsewhere.