In the book rules, what happens during the dance?

At the party, Jason hears of the dance and asks Catherine if she'd like to go. Jason senses Catherine is hesitant to accept based on his handicap, and he becomes angered. Later, Catherine matures as a person and asks Jason to go to the dance. Jason shows up, and Catherine introduces him to Kristi and Ryan. Kristi shows her true colors by being snotty about Jason, and Catherine ends up "dancing" with Jason, her true friend. In the end, Catherine has grown and has learned to find a balance between caring for David and establishing her own identity.