Alex is a sixth-grade Little League player who struggles with deep self-consciousness regarding his small size and poor athletic skills. Having won his team's "Most Improved Player" award for six consecutive years, he feels utterly inadequate on the baseball field. To cope with his insecurities and social challenges, he relies heavily on his sharp sense of humor, often acting as the class clown to deflect attention away from his perceived flaws.

T.J. is the largest student in the sixth grade and an arrogant Little League superstar. He commands attention and respect for his athletic achievements and constantly brags about his team's undefeated record. He actively bullies Alex, rejecting his attempts at friendship and targeting his physical insecurities by calling him "skinnybones."

Alex's mother and father serve as the primary authority figures in his life. They actively try to keep their son grounded, enforcing consequences when he misbehaves or tries to avoid his responsibilities. However, they frequently fail to understand the depth of his anxiety over his size and athletic failures, sometimes laughing at his slapstick misfortunes.

Brian is a sixth-grade classmate and friend to Alex. He serves as an eager audience for Alex's tall tales and comedic bits. Despite their friendship, Brian prioritizes his own safety over loyalty, quickly yielding to threats from larger, more aggressive classmates.

Mrs. Grayson is a sixth-grade teacher who oversees a classroom containing both Alex and T.J. She frequently attempts to maintain order despite Alex's poorly timed comedic interruptions and T.J.'s boastful announcements. She appears visibly impressed by the star athlete's accomplishments.

Miss Henderson is a fifth-grade teacher who presided over the initial meeting between Alex and T.J. the previous year. She possesses zero tolerance for class clowns and firmly rejects any deviations from her structured lesson plans.

The manager of Alex's consistently unsuccessful Little League team. He struggles to maintain team morale and frequently loses his patience with his less talented players. He is highly observant regarding his team's physical limitations and refuses to entertain their attempts to hide them.

Mr. Peoples is a local barber with a remarkably short temper. He lacks patience for energetic children and reacts aggressively when provoked, allowing his bad moods to directly affect the quality of his work.

Randy is a physically large player on Alex's Little League team. Due to a uniform shortage, he inadvertently exposes a lie about sizing, forcing a public and embarrassing trade.

Frankie is the pitcher for Alex's struggling Little League team. He experiences intense performance anxiety during major games and quickly turns hostile toward teammates who make mistakes on the field.

Fluffy is the Frankovitch family's pet cat. She serves as the reluctant subject of a comedic essay about Kitty Fritters cat food and frequently creates minor household chaos by eating things she shouldn't.