Book 7 United Middle School Mysteries At United Middle School, strange things are always afoot-and luckily, so are Jake, Emily, Max, and Amy. These four young investigators may seem like ordinary students, but when the principal disappears, a flag goes missing, or a mysterious clock refuses to tell time, they spring into action. From puzzling playground clues to secrets hidden in Maplewood Park, no mystery is too strange (or too small) for this clever crew. With teamwork, quick thinking, and just the right amount of middle school mischief, Jake, Emily, Max, and Amy are determined to uncover the truth-one case at a time.