Arthur began his school years at Riverside Public School, where he expressed an interest in the United States Navy from a young age. He gained an interest in aviation during a visit to the 1904 World's Fair in St. Louis, Missouri. By fourth grade, he frequently drew detailed cross-section diagrams of the . He was shy, but performed very well in school. In mid-1910, Radford moved with his family to Grinnell, Iowa, and attended Grinnell High School for a year and a half, before deciding to apply to the United States Naval Academy. He obtained the local congressman's recommendation for an appointment to the academy, and was accepted. After several months of tutoring at Annapolis, Maryland, he entered the academy in July 1912, at the age of sixteen.