For more than 30 years, Chelsea House has published curriculum-based nonfiction books for middle school and high school students. Acquired by Facts On File in 2005 and now part of Infobase Publishing, Chelsea House offers timely and engaging young adult sets and series—spanning historical and contemporary biographies, social studies, geography, science, health, high-interest titles, and more. Chelsea Clubhouse, its elementary imprint, presents easy-to-read, full-color books for young readers in grades 2 through 5.