There are a lot of young people who find the various archive sites, like the MIDI sites, and the ABC archives and learn songs from there, and not just identified folk/traditional music fans--

There is nothing easier that playing a MIDI or ABC file a few times, and then playing along with it to learn the melody--it may take a while for this to make a noticeable impact on the music kids play and listen to, but I am willing to bet that it will--Onw kid learns a song, tells a friend, and the friend learns the same tune, and then looks for something he or she can tell people about.

Of course, there no telling what the songs will end up sounding like, because kids like to experiment and make things their own, but then, that is the folk process..