Congratulations Robert     Welcome to the Amateur Radio Community
 
I think that it is a great idea.  Let me make a suggestion, when you talk to
a younger group think 21st Century, where you can talk around the world
with a handheld walkie talkie.  This is IRLP also referred as VolP.  Check
out  www.IRLP.net.
You only need a dual band handheld 5 watt radio with a keypad. I'm sure
you have one by now.  Most new amateurs buy these first, then they save
their money to buy the more expensive HF all mode radios and big antennas.
There are several nodes (repeaters) that you should be able to "hit".  There
are two in San Carlos (7540 & 8240), one in Half Moon Bay (3780), and
one in Foster City (3926).  Once you can contact one of these repeaters
then you try connecting to any of the other nodes around the world.
I suggest that you contact the owner or control operator  of the repeater
that you plan to use and advised him of your planned demo. Most owners
really enjoy working with schools and new young 'hams'.
Prior to your demo find a node that is active and try to set up a schedule
with a ham in that area.  Hawaii has some very active stations.
Most of us older guys have fixed stations and antennas and don't like to take
them down even for Field Day.
If you need more info send me another e-mail.  Good luck