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.
Continuity mistake: Carter and Cadet Haley enter the Stargate and we see them through the "puddle." When they come out on The Other Side, their positions are reversed.
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.
Continuity mistake: Stanley throws a metal nut at a 790's butt and when it hits, it shows it bounce off towards the right. When the camera cuts to the hole at the robot's feet, the nut falls into frame going left. (00:11:40)
Continuity mistake: When King mentions the two brothers' "destiny", his big feline is at Young Diabolik's side, facing King and the others. Aerial shot, and the panther is at King's side facing Diabolik. (00:05:00)
Continuity mistake: The fish that Harley uses to protect herself from the Joker changes shape and size every shot.