And Tango Makes Three by Justin Richardson and Peter Parnell has been at the top of the list 3 years in a row. Apparently the true story of the two male penguins named Roy and Silo at the Central Park Zoo who were sexual partners and raised a chick together just doesn’t sit well with some people. It’s been challenged for depicting homosexuality, being anti-family, anti-ethnic (are penguins an ethnic group?), having a religious viewpoint (what?!), and being unsuited for it’s intended age group. Check out Justseeds artist Mary Tremonte’s poster Roy and Silo:Powerful which also tells the penguins’ story.