Lisa's school friend Janey Powell makes her first appearance in the series in this episode, but looks completely different - especially that her race seems to have been changed - to her subsequent appearances.
During exterior shots of the Simpson home in this episode, the tree house is never shown. Yet the tree house is used extensively in this episode.
Marge's pearls change color between shots.
At the end when Nelson's goons are holding on to Nelson, they both have black skin color. But in the next shot, one of them has yellow skin color again.
Herman tells Bart that he needs an official declaration of war. This isn't true, as most conflicts since World War II have been fought without any such declaration.
The paper in Grampa's typewriter doesn't scroll up, even though he keeps resetting it to start new lines.
Herman misspelled "Kwik-E-Mart" as "Quick-E-Mart" on his map of Springfield.