Mac Barnett is the author of many picture books including Chloe and the Lion and Guess Again! which TIME Magazine named the no. 2 Picture Book of the year. He also writes the Brixton Brothers series of mysteries. Two of his collaborations with Jon Klassen, Extra Yarn and Sam and Dave Dig a Hole, have won the Caldecott Honor. He is also the author of The Shape Trilogy, illustrated by Jon Klassen, A Polar Bear in the Snow, illustrated by Shawn Harris and Twenty Questions, illustrated by Christian Robinson. He lives in California, USA. Find Mac online at macbarnett.com and as @macbarnett on Twitter and Instagram. Jon Klassen is the bestselling author and illustrator of The Rock from the Sky, I Want My Hat Back, We Found a Hat, and This Is Not My Hat, which won the Caldecott Medal and Kate Greenaway Medal. He is also the illustrator of The Shape Trilogy, written by Mac Barnett, and Extra Yarn, also written by Mac Barnett, which received a Caldecott Honor. Originally from Ontario, Canada, Jon worked as an illustrator for feature animated films and now lives in Los Angeles, USA. Find him online as @jonklassen on Instagram and @burstofbeaden on Twitter.