Character mistake: After the production assistant walks away from the catering table, he walks into the area where the Matthews are being interviewed. Any production assistant would know better than to just casually walk right into the shot when a live televised interview is going on.
Continuity mistake: When Shawn is loading up his backpack with food from the catering table, a production assistant emerges from the kitchen and asks him if he's part of the interview. After Shawn says he is, the assistant walks away towards the front door. When the shot changes to the couch where the family is being interviewed, the assistant is nowhere to be seen, even though he walked right into the area of the shot. When the shot changes yet again, the assistant is back by the catering table, standing with his arms folded.
Plot hole: In this episode, it is discovered through a scientific study that Eric does not dream, and in fact doesn't even register brain activity while he is sleeping. However, the season 2 episode "Wrong Side of the Tracks" features a subplot where Eric listens to a motivational tape while he sleeps so he can learn to ice skate, and he dreams of Nancy Kerrigan giving him a lesson.
Revealing mistake: When Amy steps into the living room and sees Reginald, you can see a plain white wall behind the door that leads into the kitchen, when you should be able to see the kitchen itself, which would suggest another set was placed there and they didn't move it for the filming of this scene.
Deliberate mistake: When Alan is trying to rush Amy out of the door, she yells from upstairs that she's still shaving her legs. A mere 20 seconds later, she comes downstairs wearing a dress and nylons. Even if she was for some reason shaving her legs while wearing a cocktail dress, that still wouldn't be enough time for her to clean off her legs, put nylons on and then walk downstairs.
Factual error: Throughout the series we are told over and over that Cory and Shawn have known each other forever. We see the boys and Topanga meet when they are about 6 years old, and Cory says at one point that Mr. Feeny has always been their teacher. But in this episode Mr. Feeny says Shawn was born in Ohio, lived in Oklahoma and was in and out of 5 schools by the age of 12. This implies that the boys did not meet until middle school, (age 12, when Shawn arrived in PA).
Other mistake: When Eric asks Mr. Williams why everyone is applauding Frankie missing a shot in their game of pool, Mr. Williams notes it's because no-one has ever seen two people play for three hours without sinking a shot. However, if you rewatch a couple of times the part where Frankie takes his shot and you count the balls on the table, there are only 14, not including the cue ball, when there should be fifteen. If by chance a ball was knocked off the table, then given how much the crowd was into the game, someone would have told them they needed to place the ball back on the table.
Revealing mistake: During the montage of Eric and Frankie's game of pool, at one point Frankie hits two balls that spin towards a pocket in unison. When both balls come to a stop, you can see a dent in the green ball where a wire or other device would have been inserted to keep the balls linked together.
Continuity mistake: When Cory and Shawn mistakenly believe Mr. Feeny opening the door to his cabin to be an axe-murderer, Cory throws his gloves at a nearby chair to grab something to defend himself with. One glove hits the floor in front of the chair, while the other lands on the chair and slowly falls off. A couple of shots later, the glove is back on the chair, while later shots show the other glove to be on the floor by the chair's right armrest.
Continuity mistake: During the first sequence of Eric and Frankie's game of pool, after Frankie's shot, the cue ball is shown slowing to a stop near the center pocket of the table opposite from where Eric is standing. A few shots later when Eric is taking his shot, the cue ball is suddenly near him.
Continuity mistake: Early in the episode when Cory is talking to Shawn by their lockers, Shawn closes his locker and you can see one of the straps from his backpack sticking out on the bottom-right side of the locker. A few shots later, the strap is now sticking out on the bottom-left side. About a minute later in the scene, just before Topanga comes to talk to Cory, you can see the strap is now sticking out of the bottom-middle area.