Shooter by Walter Dean Myers

Cameron, Carla, and Leonard (Len) all attend Madison High School.  Investigators want to know what kind of relationship the three friends had-- and who was really behind the deadly school shootings on April 22.  The story is told through a series of interviews with Carla and Cameron, and then finally through Len's journal.  This novel explores aspects of how well friends really know each other, why people hang on to friends in the face of obvious or even disturbing differences, and touches on prejudice in several forms.  Myers writes in his usual crisp, gripping way, and the story unfolds well.  Perhaps the most  disturbing part of the book is at the end, when Myers writes as Len in a series of journal entries.  I'll recommend this to 9th or 10th graders looking for an edgy, suspenseful read that isn't very long (this is 223 pages, mostly in dialogue format--- quick readers can finish in a couple hours).