The STEAL characterization framework is an acronym that stands for Speaks, Thoughts, Effects, Actions, and Looks. In Jerry Spinelli’s novel, Leo Borlock is the first-person narrator. In this capacity, both the terms Speaks and Thoughts can be applied to Leo throughout the novel. First-person perspective often provides the narrator’s unspoken thoughts as well as what they said out loud. In addition, dialogue between Leo and other characters can be used for Speak. An example is his conversation with Kevin about whether Stargirl was planted in their school:

This is Mica Area High School … It’s not a CIA operation.

Among his most important Thoughts are his wondering if he is becoming "goofy" and later admission of being “loopy” in his love for Stargirl after he receives her Valentine. In addition, his Thoughts are offered as his reflections from the vantage point fifteen years later.

Leo becomes important because his Actions have Effects on the overall plot. One notable Action is the interview that he and his friend conduct on their show Hot Seat, despite Leo’s initial reluctance. Another relevant Action is his conversation with Stargirl, basically ordering her to be more ordinary. The combined Effect is to reduce her acceptance by their classmates and to damage her self-esteem; both of these factors ultimately contribute to her disappearance.

Leo’s Looks are not detailed, and he is apparently an average-looking for a boy his age. He comments that, aside from Stargirl, all the MAHS students look alike, as they wear the same clothes.