The actual tree that Ian and Felicia throw their shoes up into is located outside Harvard, IL. Many shoes have been added to it since the movie.
Although the film received an R-rating (and a considerably raunchier unrated version exists as well), the source material is actually a young adult novel.
Fall Out Boy was unsure about appearing in the film until Seth Green--who is a personal friend of the band--persuaded them to do it.
There is a surprising amount of visual effects work in the film, necessitated by the fact that it was shot in Florida. Most of these visual effects involved the removal of palm trees in the backgrounds.
Director Sean Anders' younger sister, Andrea Anders, plays the trashy trailer park shopgirl who tries to defecate on Clark Duke. Sean Anders didn't find directing his sister too easy as she was half naked most of the time and their mother was on set for most of the filming.