The family visits Homer in hospital. The bow in Maggie's hair changes from blue to red, and back again.
After Homer abandons his pink car and Moe crashes into a wall, we see a view of the Simpson home with the same pink car intact.
Lisa confronts Bart about "Angry Dad" and he tells her that he will make her "Know it All Sister". During the conversation Lisa goes from holding a copy of "Angry Dad" comic in her hands to holding the same type of white drawing pad Bart is holding.
The fire alarm pull station changes color between shots when Principal Skinner activates it. In the close up shot, it is red. However, in the wide shot, it changes to blue.
At one stage, Bart and Milhouse are watching Angry Dad together when Homer runs in and starts choking Bart, and Milhouse jumps off the chair. But soon Milhouse is nowhere to be found in the rest of that scene, though he might have ran out of the house when Homer started choking Bart.