The cheating girlfriend
When Ezra takes off to the party in the novel's opening sequence, the expectation is that he will have an argument with his girlfriend which either will be resolved, leading to a passionate reunion no doubt, or which will be left unresolved, leading to a disappointment. That's what makes it so ironic when instead of having a conversation about working things out, Ezra walks in on her with another guy from school. In his fury, his attention is split and he ends up in a car accident that leaves him severely injured.
Drama and the accident
The car accident immediately elevates the drama of the novel substantially by raising Ezra's awareness that his sexual prowess and relationships are actually not the most important aspect of his existence. When he loses the ability to play tennis or run, his entire life changes. The caliber of this dramatic twist is such that when Ezra goes on living, his entire life seems unfamiliar to him. Although the school has not changed, his perception of reality has changed drastically; he is now aware of the true drama of life.
Cassidy's irony
Cassidy is Ezra's close friend and would-be girlfriend, but ironically, they meet and almost immediately get in an argument. Ezra's personality is partially responsible for this because he is a fiery and competitive person (we know this from his success in school politics). When he meets Cassidy, though, he realizes that she is a formidable opponent. She isn't a pretty face that will just help his self-esteem by association; she is a real person with a history of trauma and suffering that makes her powerful in a more important way that just athletic power.
Cooper's ironic power
Another symbol for the irony of power comes when an old poodle (not typically known for their ferocious fighting ability) manages to save Ezra from a coyote. Also, the fact that a predator is able to stalk a human being is a symbol for Ezra's frustrating relationship to his newly changed abilities. However, as if to prove to Ezra that he still has what it takes to succeed in life, the poodle succeeds and survives despite serious injuries—injuries that remind the reader of Ezra's own injuries from the accident.
Ezra's new personality
Ezra finishes the book as a dynamic character, having changed from one personality to another. When he was able to strive and succeed in sports and popularity, that need for approval drove his character, but now after trauma and tragedy have purged him of hubris, he is a new person entirely. His dog dies, which is not a comforting symbol, but Ezra knows from trauma that death is fate. Since he manages to live a happy healthy life despite his death awareness, he can be said to have attained a better kind of power than just social power or athletic prowess; he has the spiritual power to survive life's onslaught.
