“Well, pretty much the greatest non-fiction picture book author in the country.”
                        -- Esme Raji Codell of Planet Esme Blog 

“Amid an oeuvre of generally high achievement, this is Krull’s most singular accomplishment: to bring her unpatronizing enthusiasm and effective storytelling to critical thinking itself. “
-- Deborah Stevenson, Editor, The Bulletin of the Center for Children's Books