In the Fact Tracker series by Mary Pope Osborne and Natalie Pope Boyce, there’s a non-fiction companion book for each of the books in the original Magic Tree House series by Mary Pope Osborne – a series that has been delighting young readers (and their parents and teachers) for years. The Magic Tree House books introduced readers to historical events, animal stories, mythological tales, and scientific topics in an accessible, informative style. In the non-fiction companion Fact Tracker books, readers will discover more detailed information about the subjects they came across, from dinosaurs and pirates and dolphins, to Washington Crossing the Delaware, the eruption of Pompeii, the first Thanksgiving and the walk on the moon.  Combining photographs, illustration, the phonetic spelling of difficult words and short, fun and pithy facts delivered by Jack and Annie in the wide margins, the Fact Tracker books are a treasure trove of material for curious readers. The detailed information is easy-to-read, interesting and exciting. Readers will learn more than they even realize by reading these books, and come to understand that doing research is actually fun!