You can string the wire between trees for HF. For VHF, all you need is either 1m of wire (2 0.5M pieces and alligator clips) or 35 cm of wire (2 12.5cm pieces).
If you want to spend money, Yaesu has a 100W tri-band compact base-station quality model - FT-857. Carry the antennas on little spools, get some portable 6V batteries that can be hooked in series, and you have something you an hike up onto a summit. You can transmit HF and VHF.
Satellite, for now, is going to be the next thing for us. we want to build a cross dipole on a little mast and play with it. You can grab satellite images and other stuff.
It’s pretty cool, but still not something we are doing yet.
I have all the slide decks you need to get a class going for your kids for Tech. Let me know via private msg if you want them and I’ll get them over somehow (dropbox?).
Thanks for the info, I’ll contact you!