Plot hole: When Jesse and Michelle wake up in the morning, you can see that the picture Danny got was behind the couch, resting on the seat in the alcove. Later, when Danny goes into the living room and screams, Shorty is standing in the middle of the room, with his head in the picture, and the picture is facing the family. There is no way that the donkey could have put his head in that way.
Audio problem: In the contest, there is a little boy playing "When the Saints Go Marching In" on a trumpet. While this is going on, Michelle and her friends are shown backstage getting ready to go on next (you can still see the boy playing in the background). In this shot, the boy's finger movements on the trumpet do not match with the music we hear.
Continuity mistake: Watch Michelle's feet when she is jumping on the bed. At first she has two socks on, then when jumps off the bed, she has only her right sock on. Then, after Aaron says he should be president of their club, Michelle has both her socks. And when the club decides to pick the one who gets the Mighty Mutant Super Fortress as president, Michelle only has her right sock on.
Continuity mistake: In the scene where the twins take Michelle's Rigby doll, as they walk towards a dresser the boy with the doll holds it with both hands. Then in the next cut when the boy says "She didn't say that", you can see he is now holding the doll under his arm.
Visible crew/equipment: At the end of the show, when Jesse tries for the second time to make a shot from his sweet spot, he throws the ball, it misses, hits the benches and goes behind a cart (I think it's a cart). When he runs to get the ball, you can see for a quick second some equipment at the top left hand corner.
Continuity mistake: When Kimmy comes in the kitchen and sits next to DJ, there is a fork beside her plate, on the right side. In the next shot, the fork is gone. Later, when Kimmy and DJ hug, the fork is on the left side. When Stephanie reads about the baseball game an Kimmy stands up to leave, the fork is on the right side again.
Plot hole: When Danny tells Michelle to change out of her punk get-up, Michelle does, and she comes back shortly after with her hair arranged perfectly in a nice half ponytail. However, in her previous scene, she had used hairspray to make her hair all frizzy and going every which way, so it's physically impossible that she got it to be completely straight and clean again, unless she went home and washed it.