Six papers describe use of the radio for in-school and out-of-school formal education in this first volume of working papers on how radio can and is being used for education and development. Part one on in-school education contains: a Nicaraguan project to teach mathematics to first grade children (including curriculum, materials, teacher activities, problems, and envisioned solutions); an evaluation of the radio schools of Tarahumara, Mexico, begun by Jesuit missionaries in 1955, geared toward first-fourth grades; the "Radioprimaria" project headquartered in San Luis Potosi, Mexico, begun in 1970 for fourth-sixth graders in rural areas (format, materials, student participation, and gradual shift from rural to urban use are discussed); a planning study on potential of radio in elementary formal education in Indonesia (covering existing elementary education system and estimates of comparative performances and costs of alternatives). Part two deals with use of radio for distance learning: for inservice training of teachers in Kenya (distinguished by use of correspondence materials supplemented by radio broadcasts to reach a widely scattered adult population) and in Radio Santa Maria's primary and intermediate adult education program in the Dominican Republic (adapted from a model developed in the Canary Islands, Spain). (RS)