Continuity mistake: Between the first two shots of sex-ed on the second day of school, a key hanging around the coach's neck goes from hanging out of his tracksuit, to inside his tracksuit. (00:06:50)
Continuity mistake: When in Regina's bedroom, Regina takes off her pink cardigan, and puts it on a couch, just before the Plastics examine themselves in the mirror. When Regina's mum brings in drinks for them though, the top is positioned much differently. (00:18:45)
Continuity mistake: When Cady is at the Halloween party her face is painted white/gray. when she comes through the door to see Damian and Janis her face has changed from white/gray to a more green.
Continuity mistake: When Regina is being carried by some boys on the field, her "R" necklace is hanging out of her blue P.E. shirt. When they put her down it is tucked under her shirt, then when she blows a kiss it is back out again. (00:07:40)
Other mistake: The word Artist is spelled "Artitst" on the senior artist credit.
Continuity mistake: When the Plastics spot Gretchen's crush, between shots Gretchen goes from having her arm by her side, to playing with her necklace. (00:16:35)
Continuity mistake: Before Regina starts writing the nasty things about herself in the "Burn Book", there is a red pen on the floor near the book. The next shot in a closeup of the book the pen has now moved to being right next to the book. (01:00:05)
Continuity mistake: In the wings after the Jingle Bell Rock dance, Aaron has his arms around Cady and Regina. Just as Kevin leaves we can see Aaron's hand is on Cady's shoulder, but in the next shot it is down by his side.
Continuity mistake: When the Mathletes are entering the spring fling, Cady's hands are in her jacket. When the shot changes, her hands are out of her jacket and can be seen. (01:26:20)
Continuity mistake: In the scene near the end of the movie, where Janis is dancing with K.G., after Janis tells him that she's Lebanese, she smiles. The next shot, she's not smiling.
Character mistake: When the mathletes advertise their poster on the desk it reads 3.14... then they make up numbers instead of following the actual number of pi. (00:01:00 - 00:03:00)
Revealing mistake: When the Plastics are walking down the hallway together, Cady falls into a trashcan. The trashcan stays upright, but it should tip over from the way she went in, the momentum and her bodyweight. Just a few shots prior to this, a janitor, on the left side of the screen, is seen moving that trash can, so it is apparent that it is not bolted to the ground. (00:44:00)
Continuity mistake: When Regina is asking Cady about her home schooling, Regina's hair starts to fall over her shoulder, then the shot changes and it is back behind her shoulder. (00:11:00)
Continuity mistake: At the Halloween party, Karen tilts her head as she ponders cousin relationships, but in the next shot she's upright again. (00:26:30)
Continuity mistake: When Mr. Duvall takes the mic after Cady's speech at the Spring Fling, he steps with his left shoulder forward. In the next shot, his right shoulder is forward. (01:29:25)
Continuity mistake: When the Plastics are at the mall and they spot Gretchen's crush with another girl, in one shot, Karen is playing with her watch, in the next shot her arms are folded. (00:17:25)
Continuity mistake: When the Regina posts the Burn Book around school the "wanna-bees" are fighting. One girl goes, "You bitch!" and the other goes "You're the bitch!" and they start to fight. While they are fighting they jump onto a table and it breaks. If you look into the backround, you see Jason and his 2 friends turn around because they heard the noise of the table breaking and the girls fighting, and Jason's friend on the right puts his hand on Jason. When the camera changes shots his hand is on his heart.
Continuity mistake: When Regina is by her car after Cady's party, Regina says something about the Caltine bars and her boyfriend says that they are for weight gain. Regina spits it out and at one point you can see her boyfriend putting his cup up to his lips, then the shot changes to the other side of the car and his arms are down straight.
Continuity mistake: During the dance scene, the captain of the Mathletes goes up to Cady's friend Janice and starts dancing with her. At first she's smiling, but the next shot shows her with a straight face. (01:31:15)
Continuity mistake: In the 'Jingle Bell Rock' scene, right after Gretchen kicks the stereo off the stage, you see her feet, and they are both symmetrical next to each other, then when you see her again one of her feet is behind the other. Gretchen does not move at all between shots.
Answer: Precisely because he was sleeping with a student. Getting her pregnant would bring their affair out into the open and create a scandal for the whole nation to know what he was up to. Therefore safe sex was really important to him.
The_Iceman
True, but since he was spending time with her, he could make sure that birth control was being used (i.e. him using a condom). I think he was trying to appear "uptight" about sex, so he could be the least likely suspect.