Preston Mudd is a kid and minor character that only appeared in the first book. He was a very good athlete and even made "Athlete of the Month", but on the plaque, his name was put as P. Mudd. Some boys found out it sounded like Pee Mud and they started making fun of Preston for it; he hasn't been seen or mentioned since. This caused Greg to believe he shouldn't do his best in gym class. In the Popularity List, Preston is put in the 420th mark, which is just above Rowley according to the film.
- Preston's plaque in the hallways can be seen in a scene in the movie, and he is also seen when Greg is about to eat the cheese.
- He also appears in the beginning of the film when he says hi to Greg but Greg doesn't recognize him.