David A. Adler is a former math teacher and author of more than two hundred books for children. He has collaborated on several science picture books with Anna Raff, including Light Waves and Magnets Push, Magnets Pull, both named finalists for the AAAS/Subaru SB&F Prize for Excellence in Science Books. He is also the author of the Picture Book Biography series and the Cam Jansen mystery series. He lives in New York.

Rob Shepperson's editorial illustrations have appeared in The New York Times, The Washington Post, and The Wall Street Journal. The children's books he has illustrated include Thunderboom! by David L. Harrison and Blue Daisy by Helen Frost. He lives on the Hudson River, along Zimmy's route, in Croton-on-Hudson.