The shot of Eric Karros hitting the home run takes place in Shea Stadium in New York but the ball lands in the bleacher seats in Wrigley Field in Chicago.
When the Homecomming candidates are making their speeches the camera is showing close ups of Lisa while the 4H girl makes her speech. In the long shot, there is an empty chair, but in the close-up there is someone in the chair.
At the end of the movie when Lisa is in her Suburban, her hair is considerably darker and longer than it is while she's telling the story (which is in the same day).
When the girls are in the living room talking about robbing the banks, Diane is shown laying down and then sitting up and then laying down and sitting up again. However, you never see her move
In the doctor's office, Cleo places the ultrasound wand on Diane twice.
When Jack is racing for the end zone during the football game, the camera cuts to the clock counting down as if he is "racing" to get to the goal line before the clock hits zero. In a movie that was supposed to have so much to do with football/cheerleading, it's amazing that the writer/director didn't realize that since the play started during regulation, it wouldn't matter if Jack crossed the goal line with 0:00 on the clock; however, the scene is shot as if when the clock hits 0:00 and Jack was short of the end zone, the play would end.
When the girls are in the doctor's office for Diane's ultrasound, one of the girls starts moving the wand over Diane's belly, looking at the images on the screen. There is no conducting jelly on Diane, so there should be nothing showing up on the screen.
When the girls have just gotten the exterminator van you can clearly see the crew van that is pulling/filming them in the windows of each house they pass.