My two-week PDC was pretty much all theory. Very well-taught, but I was really hanging out to dig, build or do...something.
From your post, it sounds like that won't be an issue.
You strike me as a keen cook. Is food preparation going to be part of it? Nothing like shared eating for good communication!
We didn't really discuss alternative household energy options, but if there's any set up at the PDC site, a demo of wind/solar/battery-banks etc could be really helpful. I think many people are intimidated and confused by the technology.
Making
compost teas for specific requirements.
Find level without fancy gear, make a mini-swale and plant it appropriately.
Most of the stuff I'm thinking of would take too long.