Margie, an 11-year-old girl living in the year 2155, is the protagonist. She is a dynamic character, and the third-person limited omniscient narration follows her perspective. The story does not say much about Margie’s personality and interests other than that she keeps a diary and hates school. Early in the story, Margie reveals the level of her frustration with school. Although she does not directly say so, it is implied that Margie feels shame about her poor performance in geography and guilt for disappointing her mother—enough to have the County Inspector modify their mechanical teacher to instruct her at a previous grade level.

Through Margie, Asimov develops the theme of Isolation and Loneliness. Margie is a lonely, isolated child who has very few opportunities for human connection. This is evident in her “friendship” with Tommy who, at two years older than her, is not quite a peer and treats her with a sense of superiority and condescension. Despite Tommy’s dismissiveness, Margie is careful to avoid arguing with or alienating him. With no other opportunities to forge social bonds with other children, she is motivated by a need for Tommy’s approval and acceptance.