Stargirl (Susan) - this is the main character, the protagonist
Leo Borlock - this is the narrator of the story. He deals with an internal struggle to go against what the norm would approve of.
Archie - Archie is an old man who befriends the youth of the community. He is a retired professor, and offers life advice and academic teaching to any student who wants it.
Kevin - Kevin is Leo's best friend, and the host of "hot seat"
Hillari - Hillari is the antagonist, she most strongly apposes Stargirl (represents conformity in the school, and the bad attitude of the general student population toward Stargirl)
Cinnamon - Stargirl's pet rat. She carries him everywhere with her, and Leo is fond of him.
Dori Dilson - This is the one girl at Mica High School that is Stargirl's friend unconditionally.
Wayne Parr - Hillari's boyfriend. He sets the standard for student behavior at Mica High School.
