Grayson Sender, the protagonist, is a sixth-grade student at Porter, a fictional school in Chicago. She is a transgender girl who embraces her female identity throughout the course of the novel and the first-person narrator. Because other characters perceive her as a boy, they refer to her with male pronouns. Grayson describes herself as having “sandy blond hair [which hangs just past her ears], thick and straight, and [...] blue eyes” (16). She usually wears clothes like shiny basketball pants which she can pretend are pretty gowns, sweatshirts which she ties around her waist like a skirt, and long jerseys that look like dresses. Later in the story, she starts wearing girls’ shirts underneath her clothes, and at the end of the book she decides to wear them openly.

At the beginning of the novel, there is a large gap between Grayson’s real Self-Identity Versus Perception. Grayson is quiet and introverted, mostly due to her anxiety about being ridiculed or rejected. She tends to avoid social interactions, especially since her only friend Emma moved away, and initially eats lunch alone in the library. She makes an effort to befriend Amelia, a new student at Porter, but is upset when Amelia starts hanging out with other girls.