TumbleBooks are e-books that include many interactive features, such as puzzles and games for younger children. The games and puzzles reinforce lessons in each book on topics including reading, writing, math and science. National Geographic developed some of the games.
The entire TumbleBooks library of 550 titles features animations of children's books compatible with iPads, desktop and laptop computers, and e-book readers. Chapter books for elementary children do not have animation, but they have audio versions that read along with the text. Teacher editions have lesson plans, quizzes and assignments to reinforce learning after students read each book. TumbleBooks is a fee-based subscription service.