Continuity mistake: When Chief Wiggum and Homer think that the convertible Ruth and Marge are in is a ghost car, they want to hold each other. In this shot, you can see 1 small star out of the backseat of the police car. But in the next shot, from the perspective of the backseat, there is a canyon top where the star would be.
Continuity mistake: When Samantha is being introduced to the class, there is a boy in the front row on the right side that is wearing a white shirt and has brown hair. A few shots later (an overhead shot of the classroom), the boy is completely different, with a blue shirt and white hair.