At John's party when they are watching the video it shows scenes from where John asks Kate to be his girlfriend and gives her the watch but none of the other girls knew about this until Kate shows them the watch so where does the footage come from?
John scales the balconies to get to Kate's room, so he must be on the same side of the building as she is. He comes out of Coach Williams' room on one side, and then he goes into a bedroom on the other side of the hall.
Before Scott gets the salt-water dumped on him the level of water in the test-tube changes.
In the detention scene, Scott's laptop is open. When Kate says "shes hates to miss a moment of being detained," Scott slightly closes his laptop. The next shows the laptop wide open. After Kate sees John outside, the laptop is slightly closed again. When Scott describes the reactions John gets from girls, the laptop is fully closed. The next shot shows it fully opened and then he closes it.
(at around 9 mins) During the gym scene, you see Beth, Heather and Carrie sitting down after Coach Williams says "We all hate each other". As the scene cuts back to the coach who is assigning the girls to their volleyball teams, you see all three walk up behind her, and go sit down to where they were already sitting a second before.
A chemistry teacher would never let students work in the lab without safety glasses.
When John is on the sideline waiting for Kate to agree to go out on a date with him, there is a defender within 3 feet, and John does not dribble within five seconds, thus making it a 5 second violation and a turnover.
At the start of the movie, in the spelling bee, the host spells 'wrong' W-O-R-N-G. It is clear that this is intentional when Kate makes a face at the spelling.
When Heather goes to re-start boat motor after flooding it, you can see the lift-rod that drops motor in water retract back down.
When the girls hit each other with the volleyballs, the impact sounds are that of rubber kickballs/dodgeballs, not of volleyballs.
After John dumps Beth, Carrie and Heather, it cuts to Kate playing a one-sided 7" single with the 1980s Columbia Records label. However, the song heard is Hedy McDonald's 1996 cover of Paul Simon's "50 Ways to Leave Your Lover" (which was playing non-diegetically over the previous scene). McDonald's recording of the song was never released as a single, nor was it released on Columbia Records.
During the scene where John is playing basketball with a thong on, the camera shows different people watching. In one such shot while focusing on a character, they show a door with a rectangle window. As they do, somebody peeking through the window immediately pulls their head out of sight.
In the opening part of the movie, John Tucker does this fantastic dunk. As he's going back downcourt, you see the referee in the background signal a 3-pointer.
Although Beth is described as a vegan, it is implied in one scene that she consumed pizza and frosting, as well as shown eating a piece of a milk chocolate bar (all of which contain milk, a non-vegan ingredient).
At the beginning of the movie Beth says something to the
effect of "I wouldn't really kill a Bobcat, they are endangered". Bobcats are legal to hunt and not endangered.
In the last scene, the cute guy from chemistry class says "Things didn't quite work out with Alex and I" (instead of "with Alex and me").