History's Secrets of the Air and Sea investigates three perplexing historical mysteries including the Mary Celeste and disappearing planes. Readers will enjoy the story-like writing style all while learning about history, from ghost ships to AWOL aircraft. Complete with sidebars, more facts, and informative diagrams. QR Codes in the books give readers access to book-specific resources to further their learning. Aligned to Common Core Standards and correlated to state standards. DiscoverRoo is an imprint of Pop , a division of ABDO.