Timvisible

Timmy becomes invisible to avoid being beaten by Francis, but then he haunts the school and everybody gets scarred and Crocker finds out that he's the ghost and starts hunting Timmy throughout the school.

That Old Black Magic

Timmy goes to an amusement park in Friday the 13th and he figures that something is destroying the park, until Cosmo and Wanda give him special glasses to see the Anti-Fairies who are causing the problem.