Continuity mistake: In front of the locker she broke into with Daphne, Velma holds Olivia's blue ribbon in her left hand. She turns towards the locker and is surprised by Two-Mop Maggie. She is not holding the ribbon in her hand anymore, and her right hand is covered by an oven mitt. (00:37:15)
Continuity mistake: In the principal's office after melting the locker, Daphne and Velma are being scolded. Miss Piper's glasses rest on the desk in a different way depending on the angle (in the frontal shots the right side is more elevated). (00:37:45)
Continuity mistake: In close-up, Velma's "shame sticker" does not reach the topmost seam of her overalls' front. In the view with both her and Daphne, the sticker is high enough to reach there. (00:38:00)
Continuity mistake: During the chat with the two accidental lunch ladies, the strap of Griffin Griffith's bag keeps switching between in front or behind the top button of his jacket. (00:38:10)
Continuity mistake: At the beginning of the scene with the two girls on lunchlady duty, Griffin's friend Mike is juggling a football, followed by another friend with the same black letterman jacket. However, after the cut we find in that spot Griffin himself, in red, instead. One could say that maybe the ball juggler is not Mike but another guy with a crew cut, he's not wearing a bag, after all. Which brings to the subject of the other continuity mistake there; when Velma replies "You're only on top of the Bloom bracket because...", Mike is not wearing the bag that he was wearing in the other views. (00:38:25)
Continuity mistake: When Velma serves the goopy yellowness to the three Slitherin knockoffs, many continuity issues arise; the quantity of material is different in the close-up, and later varies again. Also, Mike takes his portion, but there's one in front of him right at the cut. Actually, he took Griffin's portion, but Griffin has one right in front of himself again, appeared between shots. On top of all that, the same extra (nerdy glasses and light grey sweater) walks behind the trio starting when Griffin calls himself 'new leader' and resuming several seconds later ("You mean because he tanked"), still at the same exact spot as before. (00:38:30)
Continuity mistake: Griffin is introduced as a suspect, and is shown high fiving the other guys from his cohort. In the part that follows, the paper bowl on the cafeteria counter keeps switching left and right of the opening. (00:39:25)
Continuity mistake: When the kid says "Do you wanna go out sometime?" to Lunch Lady Velma, a girl with brown hair, nerdy glasses and a shirt with rainbow stripes walks by behind him. A couple of shots later, there she is again, walking along the same path again. (00:39:40)
Continuity mistake: When the girls melt the locker for the second time, the circuit is undoubtedly positioned under the lock, but as the principal walks behind them saying "What!", you can see it poke from the side of the open door. (00:44:00)
Continuity mistake: In the school hall, Daphne and Velma find Griffin zombiefied. In the shots with the widest camera angle (same as when the two buddies to discount Draco Malfoy arrive playing ball) Velma is wearing her cloud badge on her chest, above the overalls. It's on the overalls in the rest of the scene. (00:45:30)
Continuity mistake: When Velma slams the big pile of work on the chemistry teacher's desk, the paper on top of it is a couple inches off the side closest to the professor, but it's perfectly aligned with that side after the cut. (00:48:15)
Continuity mistake: Sabotaging "Violet Johnson", Velma and Daphne are peeking from the door of the lab; the reverse shots with the hand in foreground don't match the rest - the hand looks to be operating the equipment but it is not when the table with the teacher is shown. (00:48:50)
Continuity mistake: Velma gets in the back of Mikayla's art installation looking for the power cables, and Daphne follows at distance. In the close-up, the shadow on the back of the projection screen is closer to the edge than in the preceding aerial angle. (00:49:40)
Continuity mistake: Once Mikayla is getting 'eaten' by the tube, Daphne holds Velma's arm clinging to her sleeve; at the cut, her hand is relaxed instead. (00:53:25)
Continuity mistake: Velma is holding the scooter the 'ghost' was using; her hands are placed in different positions between shots. (00:55:30)
Continuity mistake: The time counter during the call to Daphne's mom from the secret school room jumps from 5 seconds to 13, 31 to 44, 57 and 1 minute and 18, with no possibilities for time to pass during each line/cut. (00:56:40)
Continuity mistake: As they get motivated to go look for the bad guy at the end, Velma tells Daphne "I am stronger than I ever thought I was", with the strap of her bag passing inside the collar, and not outside and by the top button like in the rest of the scene. (00:58:00)
Continuity mistake: Outside Bloom, Daphne says she can hear her dad "loud and clear." The zipper of her jacket in the next shot is closed more. (00:59:00)
Continuity mistake: Daphne finds her mom sitting down and strapped to some device. She puts her bag down and reaches for the tubes, with both hands. Tobias tells her to stop and there's a cut to Velma and her, with Daphne using just one hand, the right. Next shot and she is still using both hands. (01:02:45)
Continuity mistake: In the first part of the denoument, with the two girls confronting Bloom, Velma says "Of course. Olivia was a musical prodigy." Her right hand is inside the backpack, which she is holding by the top using her left hand. Cut, and her right arm is across the bag. (01:03:40)
