Most of the gags in the clean-up scene were improvised on set by the actors.
In the book, the message on the door after the party is "Hi Rodrick!" but here it is "Rodrick Rules".
The voice of young Rodrick in the school paper flashback scene was dubbed over by Devon Bostick (Rodrick).
Jeff Kinney: During the church scene, the author of the Diary of a Wimpy Kid book series can be seen as Holly's father, walking into the church with her.