I teach in a high school and I think that getting kids playing disc golf would be great. I think several people have pointed out the logistical problems involved, which would make it difficult.
The more I think about it, though, there are bigger problems than just logistical ones. At first look, disc golf looks like a great idea for high school, but at the schools I've worked at, I just don't see it happening. Physical education should be about getting kids interested in activities that promote healthy lifestyles, but my experience with PE departments and Athletic Directors does not show this to necessarily be true. In most schools, football still rules, and all the rest is done just to appease some vocal parents. Even in my school where the football team sucks (one win in the last four years), they still get more support than any other sport. Yes, other sports like hockey, soccer and lacrosse are gaining ground, but those are still big-time local sports with lots of "boosters" and other supporters in the community. Parents and community members love to see their children play so they can re-live their own glory days.
I don't see disc golf taking off around here any time soon. I hope I'm wrong.