Hi Dennis. Do you live on the East coast or something? I (thankfully) haven’t
had to deal with people like you described since I stopped living in Germany 
My advice would be to go for a church (you may have to whip up a bit of
religious fervor if you’re not that way inclined already…), a boys & girls
club, an elementary school, public hall etc. I’ve done this quite a bit. Better
than offering to teach (I think) is to offer to do a show (or two). It’s much
less of your time and much simpler than trying to teach unicycling to a bunch of
kids (at once) who don’t have unicycles.
I’m not sure how good you are at uniing, but if you can at least freemount and
juggle a bit (not necessarily on the uni), you might be surprised at how easy it
is to put together a show that will absolutely thrill elementary school kids.
It’s very easy to learn to ride and look like you’re out of control - that’s
always a crowd pleaser (young and old). If you do manage to get a kid audience,
I can guarantee you’ll get more laughter and applause and have more fun if you
forget about trying to do anything technically good and just concentrate on
being silly. They love it when you fall off or drop in juggling - so do it. They
love it if you miss a mount, so miss it 5 times in crazy ways. You can keep kids
amused by simply trying to pick up 3 juggling clubs and each time you bend to
get the third, one of the ones you’ve collected falls out “accidentally”. It’s
amazing how long they’ll go on laughing at this. If you’re juggling, the neatest
thing in the world is to throw a ball or club so high that it hits the roof. If
you can juggle a bit, learn to eat an apple - it’s trivial (at least to do it
some ways) and kids go bananas over that trick. “Real” jugglers may scorn it,
but you can’t deny its appeal to kids. You can work for 2 years on learning to
get 20 catches with 7 balls, then you perform it and they look bored and don’t
clap. Do 2 or 3 bunny hops on a uni and they’ll go nuts. It doesn’t make sense,
but it does work If you can ride a giraffe comfortably, head towards a bunch
of seated kids and pretend to go out of control (wild arm movements, face and
yells plus wild stops & starts if you can). They’ll scream and climb all over
each other to get out of your way. Ride back out the front and turn and do it
again. It’s incredible the number of times in a row you can do this and get
exactly the same reaction - they just love it. I’m not suggesting you be boring,
just that it’s simple to be very entertaining for young kids. You might wind up
feeling pretty bloody good too. It’s a very simple and nice thing to do.
That was a long paragraph. I guess my main message is that you should go for it
and not be shy or hesitant. Don’t worry about all that legal stuff and the
chances are good that they wont either. Unless you’re on the East coast of the
U.S. or in Germany
Good luck. it’s easier than it might appear.
Terry.