Continuity mistake: When April changes into a school girl's outfit to distract Dr. Stockman's assistant, she grabs a miniskirt and ties it around the skirt that she's already wearing. But we never see her take this particular skirt off. It just magically disappears. She is also wearing pantyhose which suddenly changes to over the knee stockings.
Continuity mistake: When April is running with the canister, she has it in her right hand. The part where she has to put her hands on the car, you see it go from her right hand immediately to her left hand in the next shot.
Continuity mistake: The head and eyes of Krang's robot body change entirely after his scene with Shredder early in the movie to a different look later when he fights the Turtles.
Continuity mistake: After the outbreak Bebop and Rocksteady are talking at the bar and the level of beer in Rock's glass changes between shots.
Continuity mistake: When we first see the Technodrome building itself and Donnie is analysing it on his computer, we see a number on the screen slowly counting upwards. In one shot the number is in the 331,000 range. A few shots later, it passes by this number again.
