Summer vacation is officially over, but the excitement is just beginning for the Bobbsey family. As Bert, Nan, Flossie, and Freddie travel back home to start a brand new school year, their train trip takes a wild turn when a nearby circus train derails. Suddenly, the siblings find themselves surrounded by loose circus animals, leading to a hilarious and unforgettable rescue that includes adopting a very talented trick dog named Snap. Once the twins finally make it back to Lakeport, it is time to focus on their classes. The younger twins are starting school for the very first time, bringing plenty of funny moments and innocent mischief to the classroom. Meanwhile, the older twins are given a special responsibility to help their principal set up a brand new school museum. Everything seems to be going perfectly until the most valuable statue in the museum mysteriously disappears on opening day. Now, the four siblings must juggle their homework with a serious investigation. You will follow the children as they gather clues, interview their classmates, and try to track down the missing treasure before it is gone forever. This classic story mixes everyday school fun with an exciting puzzle to solve.