Oliver is a seventh-grader and self-proclaimed "number one rule-wrecker" at Brightling Middle School. He treats his pranks as intellectual challenges against the school's rigid authority, carefully designing stunts like coordinated toy car releases. He views the highly competent new teacher, Mr. Aidact, as the ultimate challenge to his rebellious identity.

Mr. Aidact is the unnervingly perfect new homeroom teacher at Brightling Middle School. He possesses superhuman physical reflexes and an encyclopedic knowledge of diverse subjects. His highly literal way of speaking frequently confuses his students. He declines to punish rule-breaking aggressively, instead relying on data and direct observation to manage his classroom.

Rosalie is an ambitious, rule-abiding seventh-grader who focuses on academic success and her future college applications. She finds Oliver's chaotic pranks juvenile and prefers order in the classroom. She participates in extracurricular activities like field hockey primarily to build her resume.

Nathan is Oliver's cautious best friend and reluctant accomplice in his various school pranks. He possesses an internal warning system he calls his "Oliver Alert" that signals when a scheme is likely to end in disaster. He struggles academically with math concepts, which causes him significant stress.

Steinke is an eighth-grader widely known by the unwanted nickname "Stinky." He has a reputation for being argumentative and frequently ends up in detention, feeling isolated from the traditional school system. He possesses a deep knowledge of rap music and responds positively when authority figures treat him with respect.

Paul Perkins is an older man who carries a large briefcase and acts as a "student teacher" to Mr. Aidact. Unlike typical student teachers, he never actually leads the class, instead spending his time taking meticulous notes in a notebook. He maintains a serious, clinical demeanor and often argues for stricter punishments for rule-breaking students.

Principal Candiotti is the lead administrator at Brightling Middle School. She holds a deep reverence for the school's history, having served as the captain of the 1974 state championship field hockey team. She balances her obligations to the school's staff with managing the peculiar new dynamics brought on by Mr. Aidact's arrival.

Peggy is the president of the Brightling Middle School PTA and Rosalie's mother. She is highly involved in school affairs and frequently pushes unpopular initiatives, like selling "Flaxplosion" bars. She quickly develops a romantic interest in the new homeroom teacher.

Kevin is a seventh-grader who firmly believes he is a genius. He works on the school paper and frequently inserts himself into conversations. His classmates generally find his arrogance grating.

Cassidy is an eighth-grader and the captain of the Brightling Bobcats girls' field hockey team. She is a dedicated athlete who helps rally her teammates during difficult games and leads by example on the field.

Avalon is an eighth-grader who runs the school newspaper, the *Brightling Barker*, with the efficiency of a professional newsroom. She manages student reporters and organizes school events with a serious, career-focused mindset.

Syesha Berg is a teacher at Brightling Middle School known for her exceptionally monotonous demeanor. She grows resentful of the sudden popularity of the new homeroom teacher and feels threatened by his unconventional methods.

Kelly Tapper is a teacher at Brightling Middle School who occasionally monitors detention sessions. She shares the faculty's growing jealousy over Mr. Aidact's success and worries about her own relevancy in the classroom.

Darryl is the tallest student in the school and a reluctant member of the basketball team. He faces intense pressure and verbal bullying from his father regarding his athletic performance, leading him to occasionally lash out at his peers.

Mr. Yarmolenko is Darryl's overbearing father. He aggressively pressures his son to succeed at basketball and freely mocks those he views as lacking athletic experience.

Mrs. Rostenkowski is the school guidance counselor. She appears stressed by the administrative irregularities surrounding the new teachers, occasionally engaging in tense conversations with Mr. Perkins in the cafeteria.