Girl Trouble / School Dance - S3-E18
Continuity mistake: Besides the fact that when Helga is sharpening her pencil, the desk arrangement changes, one of the students visible when she looks at Arnold is... Helga. This happens because the shot is taken from the episode "Helga's Love Potion."
Continuity mistake: In the episode when it's Kenan's birthday, Kenan and Kel are looking for Kenan's present in Kenan's parents room. As they're searching, Kel throws some of Kenan's parent's clothes all over the place. But then when Kel throws the snowglobe, there is practically no mess, but just a few clothes on the floor - less than before. Some clothes on the bed disappear as well.
Third Aunt From the Sun - S1-E7
Continuity mistake: As Mr Pool is writing 'Dermus' on the blackboard, the amount of word he writes and the appearance of it changes during shots. (00:02:10)
Continuity mistake: The six Rangers are standing together as Wolfbane is enlarged by Orbis. Kat and Tanya change places when switching from the wide shot, to a closeup of the Rangers.
Continuity mistake: Right at the beginning of this episode Kevin and the twins are making sandwiches. Lucy comes into the kitchen and kisses Kevin, then David asks where their (his and Sam's) kisses are. As this scene goes on, the shots ranging from views of all four to focal shots, David's sandwich is finished and on the (viewer's) left side of his plate, then unfinished, topped with lettuce instead of bread and on the right side of the plate. It goes back and forth between these two sandwiches. Also, at about 00:05:04 as Kevin and Lucy walk away, Sam's sandwich suddenly loses its top piece of bread. (00:04:40)
Star Check Unconventional - S2-E37
Continuity mistake: After the fight between Dexter and the large woman, the old Chinese woman who is sitting down has a collectible Barbie doll to the right of her in a glass case. After Dexter knocks the Barbie doll over and it breaks it cuts back to a shot of the Chinese woman and the doll is still in the case with no damage to the doll or the case.
Continuity mistake: The package Steve received from Mailbox is briefly visible before Mailbox comes in. You can also see a crew member's hand holding the package as Steve grabs it.
Continuity mistake: When Lois recovers in her apartment from the knock-out gas and starts swinging, Batman pushes her against her nightstand. But once she calms down and the camera makes a wide shot from the ceiling of the room, Lois and Batman suddenly crouch quite a distance away from the nightstand.
Episode #3.6 - S3-E6
Continuity mistake: When the kids are strategising Harvey takes a drink of water out of his glass leaving barely anything in it. A couple of shots later and his glass is almost half full somehow. (00:04:48)