Continuity mistake: When Kim and Shego stop chasing Ron back in Drakken's lab Shego is wearing a purple apron, then the camera moves away Shego and Kim then comes back and Shego is not wearing a purple apron, then the camera moves away again and then comes back to her and now she is wearing the apron.
Sasuke and Sakura: Friends or Foes? - S1-E3
Continuity mistake: During the scene where Naruto and Sasuke accidentally kiss, Naruto's whiskers are gone.
Forever Red - S1-E34
Continuity mistake: Serpentera is different from the Serpentera shown in Series 2, 3, and 4.
The Monsters Are on Maple Street - S1-E32
Continuity mistake: During the disturbance, the crystal punch bowl shatters, spilling glass and punch all over the table. Subsequent shots show the punch bowl still intact with no punch spillage.