The most memorable song in the film is Cat Stevens' "If You Want to Sing Out, Sing Out." This song was also used repeatedly in Harold and Maude (1971), another movie about a wealthy but troubled young man.
The film co-stars four of the Degrassi: The Next Generation (2001) kids: Lauren Collins (Paige), Aubrey Graham (Jimmy), Jake Epstein (Craig) and recurring character Ishan Davé (Linus).
In the beginning of the movie, when Charlie is playing piano with his mom, Charlie is playing the bass line (sitting on the left). High, treble notes are then heard, but his mother's hands are not on the keys. Charlie was sitting too far to the left, and would have had to reach across her body to play those high notes, which he doesn't. Therefore, those notes couldn't have been played the way they were sitting and the way their hands were.
Charlie's hair has been roughly towel dried after a fall into Nathan's swimming pool. At 1:28:51, Charlie says "No, you're her father, and she loves you very much, and you're totally missing it." Between cuts in filming this spoken sentence, Charlie's towel-dried hair changes shape.