Revealing mistake: In the shot of Skinner admiring his tater tots, he is interrupted and lifts up his tray. As he inspects he tilts his tray to at least a 90 degree angle but everything, including the milk, stays in exactly the same spots.
The Simpsons (1989)
1 revealing mistake in Principal Charming - chronological order
The Simpsons Christmas Special: Simpsons Roasting on an Open Fire - S1-E1
Continuity mistake: Lewis changes from black to yellow when Milhouse dares Bart to pull Santa's beard off. (00:14:10)
Tree House of Horror X - S11-E4
[The Simpsons are driving down a road as fast as possible.]
Homer: Dear God, it's Homer. If you really love me you'll save my life now.
[The gas needle immediately drops to empty and the car stops.]
Homer: D'oh.
Trivia: The only voice artists who regularly perform as only one character are Yeardley Smith as Lisa and Marcia Wallace as Edna Krabappel. Yeardley has also voiced different versions of Lisa (Lisa Jr. and Lisabella) in at least two other episodes.
Question: Which episodes feature the "Howling Dog" (usually used on outside shots of buildings)?