What's That Color? is a fun rhyming Questioneers board book starring Aaron Slater, Illustrator, all about colors from the #1 New York Times bestselling creators of Ada Twist, Scientist and Rosie Revere, Engineer Aaron has yellow. Rosie has red. Mix them together--it's something new instead! Aaron Slater, Illustrator and his fellow Questioneers star--as babies!--in their first-ever board book all about the dazzling world of colors. What happens when you mix yellow and blue? What about blue and red? What if you mix all the colors together? Andrea Beaty and David Roberts--the #1 New York Times bestselling creators of the Questioneers series--are back with a delightfully rhyming and vibrantly illustrated board book, the first in a brand-new concepts series for preschoolers. Readers will join their favorite baby Questioneers as they ask their first questions and explore numbers, shapes, and feelings in future board books. And discover the newest picture book in the series, Billie Jean Peet, Athlete! Check out all the books in the Questioneers series: The Questioneers Picture Book series: Iggy Peck, Architect - Rosie Revere, Engineer - Ada Twist, Scientist - Sofia Valdez, Future Prez - Aaron Slater, Illustrator - Lila Greer, Teacher of the Year - Billie Jean Peet, AthleteThe Questioneers Chapter Book series: Rosie Revere and the Raucous Riveters - Ada Twist and the Perilous Pants - Iggy Peck and the Mysterious Mansion - Sofia Valdez and the Vanishing Vote - Ada Twist and the Disappearing Dogs - Aaron Slater and the Sneaky Snake - Lila Greer and the Shrieking ShadowThe Questioneers Why Files series: Exploring Flight! - All About Plants! - The Science of Baking - Bug Bonanza! - Rockin' Robots! - Team Green!The Questioneers Ada Twist, Scientist series: Ghost Busted - Show Me the Bunny - Brainstorm Book - 5-Minute Ada Twist, Scientist StoriesThe Questioneers Big Project Book series: Iggy Peck's Big Project Book for Amazing Architects - Rosie Revere's Big Project Book for Bold Engineers - Ada Twist's Big Project Book for Stellar Scientists - Sofia Valdez's Big Project Book for Awesome Activists - Aaron Slater's Big Project Book for Astonishing Artists