Continuity mistake: In the introduction, when TJ pulls the ball off Gus, Gus is covered in gum. When they are walking into the school, the gum has disappeared.
Beware the Third Wish - S1-E31
Continuity mistake: The Wicked Wisher throws giant exploding coins onto the field TJ is on, as TJ runs towards the WW. The giant coins remain on the field after they explode, yet when TJ reaches the top of the field, there is no sign of the coins, or their remains.
Book Smart - S2-E8
Continuity mistake: The word "Puritans" is written differently on the chalkboard between shots, in the scene where T.J. is discussing Puritans with Mr. Delk.
Continuity mistake: After the Squirmese chef sets up his additional ingredients, Corky answers the video phone. During Corky's conversation, Al's kitchen can be seen with no trace of the chef or his ingredients.
Continuity mistake: The fish that Harley uses to protect herself from the Joker changes shape and size every shot.
Kessei! CLAMP gakuen tanteidan - S1-E1
Continuity mistake: Nokoru Imonoyama is looking at the dossier about the brother-in-law of their client. The chart showing the sorry state of his business looks different from the close-up when Nokoru puts it down - for instance, it's bi-color grey and white, when it was simply with white background before. (00:13:15)