Milhouse is seen watching the children's TV show (right) Teletubbies before switching to the movie commercial (although it is 7:00 pm when the horror movie commercial was on, so unless Milhouse had a Teletubbies video in the VCR or he was watching it on cable, there is no way he could have seen it, as Teletubbies doesn't come on primetime).
Otto holding up the stereo above holding is similar to the scene in the film Say Anything... where Lloyd Dobler tries the same thing to win back Diane Court.
One of the sitcoms Homer and Marge watches is called Talk to the Hand, starring David Faustino. Faustino is best known as the smart, yet perpetually dateless son, Bud Bundy, on the Fox sitcom Married...With Children.
In the Gracie Films logo, after a woman says "Shh!," the Old Jewish man shouts "Don't tell me to shush, you stupid lady!"
In the scene where Lisa is flipping through radio stations, the line "A date which will live in infamy." from President Franklin Delano Roosevelt's Infamy Speech given on December 8, 1941 can be heard.
When Wendell is among the kids seen inside the police wagon, his skin is a lot less pale than usual.
For some reason, Allison can be seen in place of Janey in the drive-through when Chief Wiggum catches them, yet the viewer does not see her running from her home or any scene before this, a similar thing happens with one of the twins in place of her when Nelson pushes Milhouse through the hole in the fence.
Additionally, the arrangement of the kids sitting when they're watching the movie changes depending on the scene.
Jimbo and Dolph are seen among the adults driving/traveling to the billboard, but earlier they were arrested for breaking the curfew and during the "Kids" song, they are seen with the kids.
During the shower scene when Barney, Carl, Homer, and Lenny all sing We Are the Champions, when Lenny lifts up his fist for two frames, his body disappears.
This episode never explains how the curfew ended afterwards, because in the future episodes, kids and adults were seen going around the town without getting in trouble, the curfew was probably lifted or something.