Buddy has to find his sister. She disappeared, so he follows her through the 13th floor (it's explained in the book) back to the 17th century. He finds himself on a pirate ship that happens to be captained by one of his relatives!
This time-travel book is pretty entertaining. It's funny and and has lots of adventure. And it has pirates! Time-travel and pirates; what's not to like? Also, since it takes place in Massachusetts during the Colonial period, you might be able to get away with it for a "Historical Fiction" book report. If you like mystery stories or if you like funny adventure stories, I recommend this one.