The Square Root of Murder

High school detectives P.C. Hawke and Mackenzie Riggs find themselves in over their heads in a challenging calculus class at Columbia University, taught by a notoriously harsh professor. When she is mysteriously murdered, pinned to the blackboard with a crossbow bolt, P.C. and Mac are faced with a complex investigation filled with numerous suspects. As they navigate the clues and tensions surrounding the grisly case, they realize that not everything is as it seems. This engaging mystery is a part of Pulitzer Prize-winning author Paul Zindel's P.C. Hawke series.