Regina's handwriting in the Burn Book changes from shot to shot.
And when Principal Duvall opens to the "fugly slut" page, the red writing isn't where it should be.
When Ms. Norbury is cleaning her shirt, the doughnuts go from inside the box to outside the box.
And when her shirt is "stuck" to her sweater, Ms. Norbury's left hand can be seen lifting it up and quickly letting it go.
When Cady scares Damian and Janis after the Halloween party, Damian tosses his popcorn. In the next shot, when Janis stands up to talk to Cady, the bowl is full again.
During the montage on the first day of school, Cady is yelled at by a German teacher...
...But when Damian reads Cady's schedule, it says she takes Spanish, not German.
When the girls go to Regina's house for the first time, Karen puts her bag on the kitchen counter. Twice.
This elephant does not live in Africa.
Neither does this Burmese Python.
At the start of the "boo, you whore" conversation, Regina has already reached the center of the doughnut. In the next shot, the doughnut is only missing a small bite.
The Ndebele tribe has fertility dolls, not vases.
While in her room with Aaron, Cady sets her cup on a pile of CDs. In the next shot, the cup moves to a smaller pile.
Bell Mobility is only in Canada.
When Cady's parents see her off on her first day of school, Cady's dad walks away...
...But in the next shot, he's still standing with Cady's mom in the background.
The girls get soaked when Principal Duvall sets off the sprinklers...
...But they're pretty dry when they're in the gym.
Coach Carr's key goes from outside his jacket to inside his jacket halfway through the sentence "You will get pregnant and die."
Cady breaks the tiara in half...
...and tosses half to Gretchen...
...and another half to Janis...
...and another half to Regina...
...and another half to Emma Gerber...
...and some little pieces to the crowd...
...and another half to Jessica Lopez...
...and more little pieces to the crowd...
...but in the end, she still has half for herself?
And those are the only "mistakes" in Mean Girls. Everything else is perfect.