Kennedy has been called "one of the pioneer folklore collectors during the first half of the 20th century". In 1937, he left the University of Florida to join the Federal Writers' Project, the federally funded Works Progress Administration (WPA) initiative created under the New Deal to fund and support American writers during the Great Depression. As part of the Federal Writers' Project, the Library of Congress hired archivists to document the diversity of American culture by recording regional folksongs (e.g., children's songs, dance and gospel music) and oral histories in many languages and dialects. For five years, Kennedy collected Florida folklore, traveling throughout Florida alongside other notable figures such as Harlem Renaissance writer Zora Neale Hurston and folklorist Alan Lomax, among others. Kennedy had a large role in editing several volumes for the Federal Writers' Project, including "The WPA Guide to Florida" and "A Guide to Key West" of the WPA's famed American Guide Series, and "The Florida Negro".