This activity is a fun way to review computation skills on decimals and fractions. Students solve 9 different problem sets in an attempt to solve a murder mystery. Students earn clues by correctly solving all problems within a particular category. Students use deductive reasoning to determine which suspect is guilty. This product includes a description of the activity, 9 problem sets involving fractions, mixed numbers, and decimals, 9 clues, student worksheets, and answer keys. This is a great way to get your students ready for standardized testing.