The show was sponsored for a brief time by the Grisby­ Grunow Company to support radio sales, and then CBS chose to retain American School of the Air as a sustaining "Columbia Educational Feature" overseen by the network's department of education. In 1940 the program was adapted and expanded to international educational markets in Canada and Latin America and the Philippines under the names School of the Air of the Americas, Radio Escuela de las Americas, and International School of the Air. Beginning in 1942, the School of the Air of the Americas was officially sponsored by the U.S. Office of War Information (OWI). In 1943 the program was deemed the "official channel for news, information, and instructions" by the OWI (CBS Program Guide, Winter 1943). In 1944 programs were also broadcast over the 400 stations of the Armed Forces Radio Service. The program was discontinued in 1948.

     A number of educational organizations and individuals lent their names and expertise to the American School of the Air. Top-level national educators, such as William C. Bagley of the Teachers' College at Columbia University and U.S. Commissioner of Education John W. Studebaker, served on the national board of consultants, and educational consultants were also involved at the state and local levels. National organizations also offered conceptual and resource support to the program.

     Each American School of the Air season ran from October through April, taking a break for the summer out-of-school months. Typically, the series offered five subseries-one for each day of the week-with titles such as Frontiers of Democracy, The Music of America, This Living World, New Horizons, Lives between the Lines, Tales from Far and Near, Americans at Work, Wellsprings of Music, Science at Work, Music on a Holiday, Science Frontiers, Gateways to Music, Story of America, March of Science, World Neighbors, Tales of Adventure, Opinion Please, and Liberty Road. Program topics included U.S. and international history and current events; music and literature; science and geography; vocational guidance and social studies; biographies; and many other topics. In 1940 CBS reported that the American School of the Air programs were received by more than 150,000 classrooms throughout all 48 states, reaching more than 200,000 teachers and 8 million pupils.

     Some radio historians typically argue that the American School of the Air was part of a political strategy in early struggles over broadcast regulation. In the 1920s and early 1930s, noncommercial and citizen organizations proposed regulation, including frequency reallocation and nonprofit channel and program set-asides, to ensure that the United States' burgeoning broadcast system would remain, on some level, competitive and in the public's hands. The outcry against establishing a wholly commercial broadcast system compelled the networks to present a clear public-interest face, replete with educational, religious, and labor programming, in order to stave off binding regulation that might compromise network program time and control. CBS's American School of the Air was a premier effort of this type.

     Educational scholars offer an alternative account of the American School of the Air. They focus on the program's role and function as an example of early educational technology and see the program as one of the first concerted experiments in education by radio, complete with supplemental classroom materials, teachers' manuals, and program guides.