Jean is Ferris' sister, she is very jealous of her brother's ability to get out of going to school. She does cover for him a bit inspite of this. In the film's end she meets a boy at jail and that pretty much is the highlight of her day in comparision to Ferris' day of adventure.

This is the Principal of Ferris' school. He has grown tired of watching Ferris skip school and cause other mischief without being able to catch him in the act. Mr. Rooney becomes desperate and even travels to Ferris' house to try to catch Ferris in the act of faking a sickness. In this adventure he loses his shoes in the mud and is chased by a dog.

This is Ferris' mother, she is unaware of her son's frequent skipping of school. Principal Rooney phones her to tell her about all of the skipping, but as they are talking Ferris alters the school's computer records so it appears that Ferris has not been skipping at all. Needless to say Katie has a fun time arguing with Mr. Rooney.

Grace is the streotypical sweet school secretary that answers the phone and does other tasks for Principal Rooney. In short Grace is Rooney's personal assistant and lackey.

Garth is a character that Jeanie Bueller meets after going to the police station in response to her claim that the school Principal who was sneaking about the house was a burglar. Charlie Sheen who played the thug in the prison scene also played with the actress playing Jeanie Bueller in the classic movie Red Dawn.

Simone's major contribution to the film is her explanation of who she heard that Ferris Bueller is sick from. She explains without skipping a beat that "Um, he's sick. My best friend's sister's boyfriend's brother's girlfriend heard from this guy who knows this kid who's going with the girl who saw Ferris pass out at 31 Flavors last night. I guess it's pretty serious."