His research interests lie in 20th and 21st century African American writers and illustrators of literature for children and youth. His research is concentrated in the areas of cultural aesthetics, reviews of literature texts, and interviews of acclaimed authors and illustrators. His articles, reviews, and interviews have appeared in Language Arts, The Reading Teacher, Journal of Children's Literature, Children's Literature in Education, and the Children's Literature Association Quarterly, among others. Darwin is chair of the 2007 Coretta Scott King Book Award jury, a member of the advisory board of the Children's Defense Fund's Langston Hughes Library in Clinton, TN, and co-editor of Exploring Culturally Diverse Literature for Children and Adolescents: Learning to Listen in New Ways.