Philosophers Stone Mistakes
- When Harry tells Hedwig he can't use magic to let Hedwig out, the key can be seen in the lock.
- When Hermione first meets Harry and Ron, she fixes Harry's glasses. But two or three scene cuts earlier there is no tape around his glasses. It reappears in time for Hermione to fix.
- After Harry is sorted into Gryffindor at the start of term feast, he sits down on the right side of the table next to Ron. When the feast appears, Harry is on the other side of the table, next to Hermione.
- In the flying class scene, Hermione's hair is crimped. Later, when you see the class looking at Neville after his fall, you see that her hair is straight. The very next shot she's in, her hair's crimped again.
- When the troll is about to swing at Harry with his club for the third time, Ron levitates the club. When the club falls, it hits the troll's head with a loud thump, and then falls to the ground, but there is never any sound of the club hitting the ground.
Chamber of Secrets Mistakes
- At the beginning of the movie Harry talks to Hedwig, apologizing that he can't let her out of her cage because he isn't allowed to do magic outside of school. If you look closely, the key is in the lock.
- When Harry curses Draco during their duel, Draco falls to the floor, his hair messed up. When he gets back up, his hair is slicked back again.
- When Ron steps into the fireplace to use Floo Powder, he supposedly takes a handful of the sand, but if you look closely, you'll see no sand slipping out; he simply crinkles his hand. But in the next scene, he somehow has the sand, dropping it into the fire.
- When Harry and Ron are in the girls’ bathroom and find Tom's diary, it is night. Right before they go into the bathroom, it’s daytime -- you can see the sunlight coming through the windows.
- When the Anglia falls out of the Womping Willow and drives a little bit away with Harry and Ron, it leaves no tracks: There are marks from the wheels only when it drives away on its own.
- The entire Herbology class should have heard the Mandrakes because Seamus and Professor Sprout carry on a conversation while wearing the earmuffs.
Prisoner of Azkaban Mistakes
- As the Fat Lady sings, three girls are watching from the picture on the right. The girl in the pink dress starts flinching before the Fat Lady hits the bad note.
- When Snape is substituting for Lupin in Defense Against the Dark Arts, Hermione's hair keeps changing. Sometimes it is completely down and others times it is half back.
- When Harry attacks Draco in the snow at the Shrieking Shack you can see Draco flinch before the first snowball even hits him.