Visible crew/equipment: If you look really, really, really close in the background as the killer throws Cici off the balcony, you can see someone sitting in a tree, wearing black, with a camera.

Revealing: Just before the cop gets impaled through the head by the pole, you can see that it is obviously a dummy. (Easier to view in slow motion)

Revealing: In the opening sequence when Omar Epp's character gets a nasty knife wound to the head. Watch carefully and you can see the retractable blade popping back out when he pulls his head away. It is very quick though!

Factual error: If the glass in the cop car is weak enough for the killer to smash it without hurting his hand, shouldn't it be weak enough to break when he throws the cop against another window hard enough to draw blood?

Continuity: When the Sheriff writes "Cici Cooper" on the chalkboard, between the closeup and wideshot of him writing, the handwriting and location of his writing dramatically changes, and the words "Maureen Evans" and "Phil Stevens" above, also change too.

Continuity: When Sidney and her friend get into the police car to be taken to protection, Sidney sits on the driver's side. When the car crashes, she is on the passenger side.

Other: The book Gale Weathers wrote seems to know lots about the conversation Casey (Drew) had with the killer in the first scene of Scream. But seeing as both Casey and the killer died in the film, how could Gale have known so much about the conversation Stacey had on the phone?

Audio problem: When Dewey is being stabbed up against the soundproof glass, you see a shot of Gail shouting "No." You can see a reflection of the killer in the glass standing motionless, but you can hear Dewey being stabbed.