Source: Station websites and related websites, unless otherwise noted.
Where did your public-radio station come from? If it acquired a license in the 1940s or 1950s, there's a good chance it was started for instructional purposes. Many stations created educational programming that was used by students in the classroom.
As reporter Adriene Hill chronicles in her story on the roots of public radio, over-the-air education fizzled out after television came along.
The map above shows nearly 100 radio stations that had been granted a broadcasting license as of 1951. They include universities, school boards, trade schools and even a public library. The stations were required to have an educational purpose. It could be anything from teaching broadcasting, to creating programs to be used in the classroom (some stations broadcast only during school hours), to simply playing classical music (apparently it had more to teach us than other types of music).
The red markers show stations that are now defunct; the green ones are still broadcasting; and yellow is for stations broadcasting under different call letters.
By clicking on a marker, you can read a little more about the station's history
In general, most stations that were run by school boards are gone. Many of the stations that were licensed to universities have become NPR member stations, and are only nominally affiliated with the institution that was granted the license.
At the college level, there are still some student-run stations and some are still creating instructional material. There are even a few high-school radio stations that have survived.
We know there's a lot more public-radio history that we've missed, so please fill us in. We'd also love to hear from you if your station is not on the map, but was founded for over-the-air instruction.