1. The weird homeschooler spells out the word "xylocarp" at the beginning of the movie, but did you know that a xylocarp is a hard, woody fruit?
2. Mrs. George must actually think she's a member of the Plastics, because she's wearing pink just like them on Wednesday.
3. Even before Cady replaces Regina as head of the Plastics, it looks like she's making moves — she's wearing a matching C necklace to Regina's R and none of the others sport similar accessories.
4. It might have been an error, but it's weird Cady took her "98" differential equations test on October 14. Ms. Norbury handed it back AFTER the talent show, which we know took place November 27. That's at least a month and a half later!
5. Not only does Ms. Norbury spill soda on herself at the beginning of the movie, but it's also in one of those green and purple paper cups everyone drank from in the '90s.
6. It looks like Karen ~customized~ her gym class outfit by cutting off the sleeves of her shirt.
7. Not only did Janis and Damian label the tables in the cafeteria, they even mapped out the lunch line — food options include "Spam," "Mystery Meat," and "Fish Sticks."
8. The Plastics seem OBSESSED with drinking Perrier — they're all sipping on it when they first meet Cady...
...but Gretchen and Karen switch to Diet Coke that Wednesday.
9. Gretchen says "irregardless" when she's explaining to Cady why she can't date Aaron, but that's NOT a real word!
10. "Milkshake" by Kelis is playing when Regina drives the Plastics to her house, and it's actually diegetic music — Kylie, her little sister, is dancing to the music video in their living room.
11. Janis and Damian are watching Friday the 13th when Cady walks in, but it also looks like they watched Harry Potter and the Chamber of Secrets earlier in the evening.
12. Remember how hoop earrings were Regina's thing? Well, Cady's sporting a pair at her house party — after Regina's been kicked out of the Plastics, of course.
13. Gretchen shouldn't be TOO embarrassed about getting diarrhea in Barnes & Noble — needing to poop in bookstores is actually a common phenomenon.
It's called the Mariko Aoki phenomenon.