Stim: If the way that you sang the songs in the book, what ever songs they were called, is the way that the music teacher taught, it probably doesn't have much to do with the folk process (but maybe still some)
If you sang a slightly different melody than was in the book, or left out or added some verses, or, especially, if you used different names in the song and made jokes out of some of the lines or verses, then the folk process comes into play.
Thanks for answering that Stim. The songs in the books were indeed what we called folk music and it was pretty universal. Music teachers would not teach this stuff in those days - this was folk music. It is what was sung in the schools and at parties and get-togethers - often organized for the purpose. Any process here would be a matter of cultural development and not really effecting the music.
In one sense, there was actually process. The melodic content and harmonic structure was a direct development of Germanic musical traditions as it had come to fruition in the Baroque.
That said, these songs (because of their universality during those generations) were much used as the basis for made-up songs at weddings and similar events. Perhaps this could be better described as popular music even though it is what was called folk. It is also noteworthy that there was almost never any accompaniment - except occasionally piano at public gatherings.
Perhaps Denmark doesn't actually have a folk music in the sense that it is being discussed here. Perhaps Denmark (outside of art music) only has historical, and popular. A Wikipedial entry on the Danish cultural canon doesn't even mention "folk" music and only lists that to which I am referring. (see here)
I don't mean to derail Larry's query, but it seems to me that there is something here which is specific to English and American culture which would be useful to pinpoint if any discussion of what is, or can become, "folk" is to have any meaning.