The film takes place from September 3 to September 7, 2001.
(at around 13 mins) Alex D. Linz described his experience of being thrown into a pool of mud by saying "This has got to be one of the most disgusting experiences of my professional life."
Max was supposed to be somewhat flustered talking to Jenna after walking into a door while looking at her, but Alex D. Linz flubbed his line and nearly got the giggles (12:02). The filmmakers liked the effect and put that take into the film.
In Max's flashback about how the bullies were plaguing the school, there was a brief scene where Megan tells Dobbs that she keeps her money in a piggy bank that "looks just like you." This was left over from a deleted scene where Dobbs tries to get Megan to give him her lunch money, but then she refuses (by sarcastically telling him the above line), which then results in him stealing her clarinet from the locker as retaliation.