Belmont High as a symbol
By putting Hayley in the most normal environment imaginable, she becomes subject to something completely out of the ordinary from her own sense of normal. The school is a symbol for the inversion of Hayley's character. She is the inverse opposite of all the kids in these classes whom she resents. She believes the school is like a trap designed to torture her, but what is really happening is that her sense of "normal" is being exposed. She has no sense of home in the high school. She feels she is in hell.
The teachers and students
In the streets, there is absolutely no excuse for trusting adults. She knows that. The adults she meets in the streets with her mentally unstable father—those are not typically people that should be obeyed. Those people are extremely dangerous. That is the dynamic that is represented in her hatred for teachers and students. She thinks teachers are snakes who use false authority to trick stupid kids into doing what they want. This is a symbolic reminder that her opinion of "knowledge" is shaped by what helps her survive her own "real world."
Finn as a mediator
Finn is a friend who believes that Hayley is a good person with a different life than most. This makes him a symbol for forgiveness and acceptance, and because he stands between her and the masses, he is also a figure for her adaptation and enfranchisement to the group. He is a symbolic mediator. In archetypal language, he is a savior who can have one foot in Hayley's sense of "normal" and the other foot in the school's community.
Trish the anti-mom
Hayley is subjected to the chaos of Trish who arrives just as Hayley starts fitting in and getting a grip of her situation. She represents the opposite of motherhood. Instead of demonstrating the motherly notion of security and nurturing, Trish brings her own internal chaos into Hayley's life. The dilemma represents a transformation in Hayley's life, because Hayley begins to see that her home life with her father is truly unsustainable.
The power inversion
Through motif, the reader can see who the real adult is in Hayley's family. Part of the reason she hates teachers is because they try to put her in the role of a child, which is not where she feels she belongs. She feels she belongs in the role of authority that they occupy, because in her home, that's what she provides to her family. Trish comes in and competes with her for authority over her dad, but under Trish's influence, the father slides into chaos, and the motif is complete when Hayley begs her father not to kill himself, the ultimate inversion of responsibility.
