Revealing mistake: After Splinter releases the nunchaku from Shredder's spear, he falls from the building's ledge. But notice how Shredder stops abruptly right before the series of shots which show him taking the long fall into a trash compactor, indicating that he actually lands on a mat. (01:23:00)
Visible crew/equipment: At the end where all of the turtles are complimenting themselves, Splinter's puppeteer is visible when he walks onscreen to say "Cowabunga" (full screen version). (01:27:00)
Other mistake: In the music within the ending credits, the lyrics incorrectly state that Raph is the leader of the group when all Turtle fans past and present know it is Leo.
Visible crew/equipment: When Splinter throws Shredder over the wall, Splinter's puppeteer is visible. (Full screen only).
Visible crew/equipment: When Shredder is charging at Splinter with the spear the edge of the backdrop and a hanging wire are visible at the top of the screen. Full screen version.
Revealing mistake: In the scene where Raphael is thrown through April's skylight after being attacked by a few dozen members of the Foot, the other Turtles and April check on him. As Donatello and Leonardo look him over, they lean on his shell, bending it with great ease even though a turtle's shell is supposed to be almost as hard as rock.
Revealing mistake: A lot of times in the movie, when the turtles' mouths are wide open, you can see the cast. An example of this is the scene when Raphael wakes up in the bath tub and Leo hugs him. When Donatello tilts his head back and laughs you can see eyes, a nose, and a mouth within the mouth of the costume.
Revealing mistake: When Michelangelo and the foot soldier are having their nunchaku duel, you can see the foot soldier's weapon is foam padded so as not to injure the performer.
Revealing mistake: During the Turtles fight with Shredder watch carefully, the blade on his left hand bend back, made of rubber.
Continuity mistake: When Splinter is holding the Shredder over the building's ledge, the cord on Mike's discarded nunchaku changes position in relation to the spear's point. It moves closer to the point for a single shot, then moves back to its original position in the subsequent shots.
Visible crew/equipment: Just before the ceiling collapses on the antique store a boom operator can be seen on the right hand side of the screen.
Continuity mistake: When Splinter flips Shredder over the edge of the building, Shredder pulls a knife and throws it. When Splinter catches the knife, he catches it with his right hand; in the next shot, Splinter's right hand releases the nunchaku and Shredder falls. The shots are out of order.
Visible crew/equipment: When Michelangelo retracts his head from a sword blow into his shell, you can see a crewman's hands under his armpits, holding and moving his upper arms.
Continuity mistake: When the turtles are fighting Shredder, in the second go-round so to speak, the order is Donatello, Michelangelo, Raphael, and finally Leonardo. When Leo is knocked to the ground, the next shot shows him leaning over the edge of the building as Donatello walks into shot holding his shoulder as if he just did battle.
Continuity mistake: When Raphael knocks down Casey Jones and enables the purse snatchers to escape, they are getting up off the ground and running away. In the next shot, they are again seen getting up off the ground and running away.
Character mistake: When Raphael is chasing Casey Jones after their fight he vaults over a taxi hood, never takes his eyes off Casey, but he somehow loses him.
Suggested correction: 2 things are happening; a shell backed stocky Raphael is chasing a lighter human athlete Casey. Casey has freedom of movement, whereas Raphael can't stray much from the shadows in hiding. :-) A knocked out Casey wouldn't be helping the Turtles out of the next evening with that memorable entry so I'm glad Raph lost the chase.
Continuity mistake: During the fight in April's apartment, The Foot Clan member swings his weapon at Donatello and misses knocking out the power as seen by sparks which causes the fire. Somehow April's answering machine still works, though.
Continuity mistake: When Raphael angrily leaves and practices his Ninja moves on the roof, he appears on a white building. When he is thrown through the roof down to the other Turtles, it is still a white building. The building in which the Turtles fight The Foot and catches fire is the "Second Time Around Antiques and More" shop where April lives which is brick, not white.
Other mistake: After Leo's failed attempt of fighting Shredder for the first time, Mikey and Donnie then play Rock, Paper, Scissors to see who fights Shredder next. It then cuts to Casey talking to "The Foot" where you can hear Mikey fighting Shredder. The next scene shows all four Turtles in a huddle regrouping, breathing heavy, and out of breath. According to what we heard, Donatello shouldn't be out of breath as he has not fought Shredder for the first time yet.
Continuity mistake: As Casey draws his cricket bat, his bag is empty. A moment later, as he runs off, he has all of his weapons back.
