Mac Barnett is a New York Times best-selling author of several books for children, including Sam and Dave Dig a Hole, the Shapes Trilogy, and many others illustrated by Jon Klassen. He is also the author of Just Because, illustrated by Isabelle Arsenault; A Polar Bear in the Snow, illustrated by Shawn Harris; John’s Turn, illustrated by Kate Berube; and Twenty Questions, illustrated by Christian Robinson. Winner of three New York Times/New York Public Library Best Illustrated Children’s Book Awards and the Boston Globe–Horn Book Award, Mac Barnett lives in Oakland, California.