"Stubborn as a mule" often describes an individual who is headstrong and stuck in his or her ways. Stubborn as a Mule dives into mule characteristics and behavior to investigate if there is truth behind this common expression. Easy-to-read text, vivid images, and helpful back matter give readers a clear look at this subject. Features include a table of contents, infographics, a glossary, additional resources, and an index. Aligned to Common Core Standards and correlated to state standards. Kids Core is an imprint of Abdo Publishing, a division of ABDO.