Mac Barnett is the author of several books for children, including Extra Yarn, illustrated by Jon Klassen, which won a Caldecott Honor and a Boston Globe-Horn Book Award, and Sam and Dave Dig a Hole, winner of the E. B. White Read Aloud Award. With Jory John, he is the co-author of the New York Times best-selling series The Terrible Two. Mac Barnett lives in California.
Jon Klassen is the author-illustrator of I Want My Hat Back, a Theodor Seuss Geisel Honor Book, and This Is Not My Hat, winner of the Caldecott Medal and the Kate Greenaway Medal, and We Found a Hat. He is also the illustrator of two Caldecott Honor books, Sam and Dave Dig a Hole and Extra Yarn, both written by Mac Barnett. Jon Klassen lives in Los Angeles.