I have a little experience doing non-ag related hacker-ish camps with teens, so could try to find some resources, send ideas your way about some ways to structure activities, examples of activities that worked well (or didn't). Contact me if it would be helpful - would be good to know what kind of fabrication and digital technology you'll have available, how long each day you plan to work with them, and what age/expereince levels you expect.
for a wonky perspective, this is also an interesting chapter: http://www.blikstein.com/paulo/documents/books/Blikstein-TravelsInTroyWi...
It spends some time with theory of working with young people and technology, but also has some more concrete advice and examples of how programs have been run.
Some general principles he describes include:
-- Identify a community-relevant generative theme (you already have this! sustainable agriculture, which can be refined through the student's research into local issues and brainstorming)
-- Depart from the community's technological culture and expertise as a basis for introducing new technologies
-- Use mixed-media approach, in which high and low-tech, on and off-screen, high and low-cost, and expressive as well as fabrication tools coexist
-- question taken-for-granted practices and mindsets (for example, about abilities and ways of treating of young people)
Another important component is bringing in experts and actual practitioners - farmers, designers, fabricators - to not just give feedback, but join in the work for at least parts.
Sounds like a great project. Would love to hear more about it as you move forward!
A couple lines from the article that I am often reminded of when teaching and building stuff with young people:
-- "choosing a curriculum is an intrinsically political act"
-- 'I anticipated that the students would find this access to the equipment highly appealing. I was again wrong. Even though students seemed excited, some were afraid to use the equipment and these anxieties were only further stoked by some teachers."
A "non-farmer ally' here - an educator and ed researcher who has been involved with ag stuff, bikes, and community organizations over the last handful of years. Am replanting my garden rows in Oakland, CA, and listening in, looking for opportunity to lend a hand. Hope I can find a way to contribute - helping get people together, linking up human and financial resources, develop ideas... just thinking alongside everyone.