The Eskimo - S5-E13
Character mistake: In the opening scene, Cory remarks that they have been in high school for 4 years and there's nothing left for them to be taught. They began high school in 7th grade and are now midway through their senior year, so they have actually been in high school for 5 and a half years.
Suggested correction: There's a difference between being at the same school and being in high school. For most students, high school is 4-years long (9th-12th grade). When I was in kindergarten, I went to a K-12 school. If I graduated from that school, I wouldn't have said I was in high school for 13 years.
It's openly stated numerous times beginning with season 2 when they are in 7th grade that they are now in high school. The school is even called John Adams High School, and not something like John Adams K-12 or anything like that. I remember being baffled by this growing up, because high school for me did not begin until 9th grade, and even then, we didn't attend an actual high school until 10th grade. It may be unconventional compared to real life, but the show firmly established that they were in high school starting with 7th grade.
Continuity mistake: When Cory is saying to Lauren "Well, today I guess you're stuck with me," he slightly raises his left hand and then sets it back down on his left knee. When the shot changes, his left hand is suddenly resting on the couch cushion between his legs. (00:05:03)
Revealing mistake: When Topanga is picking up the letter off the ground, you can tell the snow isn't real because it doesn't behave like real snow and run together when she scrapes the letter against it. It looks more like shredded paper being swept aside. (00:20:38)
Torn Between Two Lovers (Feeling Like a Fool) - S5-E16
Continuity mistake: When Eric is saying "You think I should be a teacher," Mr. Feeny has his hands on his hips. When the shot changes, his arms are down by his sides. (00:15:42)
And Then There Was Shawn - S5-E17
Continuity mistake: When Shawn is grilling Kenny about asking to borrow Topanga's pencil, sometimes there is a female student sitting directly behind Angela with an open book on her desk, and other times the desk is unoccupied altogether. (00:00:21 - 00:02:40)
And Then There Was Shawn - S5-E17
Continuity mistake: After Eric rips the receiver and cable off the pay phone, at first he is holding the receiver in his right hand and the cable in the left. A couple of shots later, the receiver and cable have swapped hands. (00:15:15)
And Then There Was Shawn - S5-E17
Revealing mistake: When Shawn unmasks the killer and it is revealed to be himself, you can see that the body double that does the unmasking has sideburns and extra scruff on the back of his neck, making him noticeably distinct from Shawn. (00:18:17)
And Then There Was Shawn - S5-E17
Continuity mistake: When Feeny appears in the hall, he has his hands in front of him, and he is holding them. When Shawn touches him on the shoulder and Feeny falls on his knees, his hands are still in the same position, but when he is shown lying on the ground, his arms are now be his sides. Feeny was dead, so there is no way that he could've moved his arms.
If You Can't Be With the One You Love... - S5-E18
Continuity mistake: When the transient is asking Cory if he's a cop, he points his right-hand index finger at him. When the shot changes, his index finger is curled onto his thumb. (00:08:20)
If You Can't Be With the One You Love... - S5-E18
Continuity mistake: When Shawn is cracking open his beer, he grips the top of the paper bag between his forearm and upper arm, with the top of the bag level with his shoulder. When the shot changes, the bag is suddenly lower. (00:09:15)
Factual error: The Starry Night painting that characters look at in the Van Gogh exhibit is mentioned as being the original painting itself. However, if you compare the painting presented in this episode with the real-life painting that is displayed in the Museum of Modern Art, you can see that it is an imitation, as the colors are brighter and the little details in the painting are not as prominent.
Factual error: When Topanga and Ricky are looking at the Starry Night painting, Topanga reads from her pamphlet and says it mentions Vincent Van Gogh became religious around the time he painted it. Van Gogh grew up in a religious household, with his father being a minister of the Dutch Reformed Church, and Vincent himself actually had a desire to become a pastor. On the contrary, however, when he painted Starry Night, although he still believed in an afterlife, he was actually disillusioned with religion.
Continuity mistake: After Topanga angrily walks out of Cory's house, he gets out of his chair and says "She really left," with his arms and fingers outstretched. When the shot changes, his fingers on both hands are curled into loose fists. (00:12:40)
Graduation - S5-E24
Continuity mistake: When Jack is showing Shawn the framed caricature drawing, both his hands are holding the frame around the middle of each vertical side. When the shot changes, his left hand is suddenly holding the frame by the bottom corner. (00:06:10)
Graduation - S5-E24
Audio problem: When Mr. Feeny is reading off the names of all the graduates, you can hear reverb in his voice to indicate that he is speaking into a microphone. The problem is there is no microphone in front of him. You can see Eric holding the microphone next to him and singing into it, with no audio. If that microphone is turned off, then Feeny's voice should not be amplified. If the microphone is on, then we should also hear Eric as he is singing. (00:19:38 - 00:20:56)
Graduation - S5-E24
Factual error: In the episode Class Pre-Union, they were the class of 2000. In the episode Graduation, they were the class of 1998.