Who Stole The Mystery Books... The start To A New Unit

The Mystery Books were Stolen from 
Ms. Wright's Third Grade class 
just as they were about to start the MYSTERY Unit.
They'll have to follow the clues  to catch the crook.

                         A Mystery must have:
                            1.A crime or a problem
                            2.Clues
                            3.False Clues( Red Herring)
                            4.Suspects