Read the adventure and track the facts--it's two great ebooks in one! Join Jack and Annie as they travel to ancient Japan in Magic Tree HouseĀ® #5: Night of the Ninjas. Then uncover the facts behind the fiction in Magic Tree HouseĀ® Fact Tracker: Ninjas and Samurai. It's two favorite ebooks in one! Find out why Mary Pope Osborne's #1 New York Times bestselling series is such a hit with kids, parents, and teachers around the world.