Graham wrote several biographies in the 1940’s and 1950’s directed at young adult readers; most of them were about African-American subjects. Her work received a variety of responses. Many readers warmly appreciated her positive, even sentimentalized portraits, while others rejected them as oversimplifications of complicated individuals. Her 1947 biography There Once Was a Slave : The Heroic Story of Frederick Douglass, for example, received the Julian Messner Award but was attacked as a failure by a young James Baldwin in a magazine essay. Her biography of poet Phillis Wheatley was very popular; it was in its fourteenth printing in 1977 (the year of Graham’s death). Other subjects of her biographies included Booker T. Washington, George Washington Carver, Paul Robeson, and Pocahontas. She also profiled leader W. E. B. Du Bois, who later became her second husband.
Graham’s goal was always to instruct and inspire as she told her subjects’ stories; Banneker’s life was well suited to this purpose, as he symbolized the triumph of determination and simple ingenuity over cultural and social disadvantage. Being set in a vibrant time, when the United States was in its infancy, the story also presents a rich historical context, including such things as the Declaration of Independence, the revolutionary war, and the evils of slavery and the slave trade. In all of her books, sentimental though they may be, Graham makes the past come alive while she imparts important lessons to young readers.