Irrational Numbers — Robert Spiller

When her phone number is found in the pocket of a murdered student who previously came out of the closet in a speech to his classmates, full-time math teacher and part-time troublemaker Bonnie Pinkwater is drawn into the case. Joining forces with the school's principal, Lloyd Whittaker, Bonnie begins to investigate -- only to have potential suspects start turning up dead. Using logic and math as a backbone of her investigation, Bonnie must catch the killer before she, too, is added to the growing list of bodies in this chilling casebook full of stunning twists and turns.