"Magic Tree House" is a popular children's book series written by Mary Pope Osborne. The series follows siblings Jack and Annie as they discover a magical tree house filled with books that transport them to different times and places in history. Each adventure teaches them about various subjects, including dinosaurs, ancient Egypt, and the American Revolution. The books are designed for early readers and combine elements of fantasy with educational content. With over 30 titles, the series encourages curiosity and a love for reading while introducing young readers to important historical events and figures in an engaging way.