Katherine Alice Applegate (born October 9, 1956), known professionally as K. A. Applegate or Katherine Applegate, is an American young adult and children's fiction writer, best known as the author of the Animorphs, Remnants, Everworld, and other book series. She won the 2013 Newbery Medal for her 2012 children's novel The One and Only Ivan.Applegate's most popular books are science fiction, fantasy, and adventure novels. She won the Best New Children's Book Series Award in 1997 in Publishers Weekly. Her book Home of the Brave has won several awards. She also wrote a chapter book series in 2008?09 called Roscoe Riley Rules.