You are going to be limited by band regulation. In the US, I think you are looking at MURS, CB, FRS, GMRS, and Ham radio bands.
Higher frequencies, such as UHF FRS/GMRS bands, foliage and other structures will attenuate the RF signal. Lower frequencies, such as HF CB/Ham bands have longer ground propagation and can benefit from "skywave" atmospheric reflection.
I think 80 meters and lower provide fairly reliable ground wave propagation over long distance, specially at night.
I remember PSK31 was a popular digital mode.
I like 2meter ham band for the repeater network where I am, and APRS is a lot of fun (check out APRS.fi). VHF can benefit from tropospheric propagation - where the radio wave can reflect lower in the atmosphere due to differences in air temperature (air inversion zones).
UHF Ham/FRS/GMRS are also reliable HH bands, but shorter line of sight range.
I noticed that you did not refer to Boy scouts. It's a bit sad in that regard, what is happening there (OT)...
I would give scouts FRS radios. maybe a 2-mile line of sight range, over water. Or about 1 mile max in the woods.
GMRS is on the same band and can use more power and external antennas - so a 50W base with antenna 50 feet up will give a good range, probably up to 20 mile max radius, or longer if using directional antenna, to a mobile HT. Remember the foliage though.
Without restriction, I might opt for the 6 meter ham band. Antenna's are a bit larger, but still manageable, and the wave will propagate better through the woods and terrain. Lower bands have antenna issues for you.
Oh, and SSB is probably a more efficient voice mode for you.