Are you familiar with the Southern California family that raises 6,000 - 10,000 pounds of food a year (350 varieties plus chickens and goats) on their 1/5 acre city "homestead?" For individual families, this might be more cost-effective than the aquaponics, and easier for the average person to handle.
Check out their site:
www.pathtofreedom.com. Also, see the Freedom Garden challenge, similar to the WWII Victory Garden concept. There's lots of solid inspiration on their site, as well as a great garden forum.
Their garden area is 1/10th of an acre, 66' X 66'. They built beds using mostly found materials, over time, and steadily built up their garden soil with compost and manure from the animals. They have increased the variety and number of pounds grown on this small plot. The family sells their produce to restaurants, as well as for their own use. Once you build your soil, and start saving seeds, the cost to maintain this type of garden would be miniscule. A family of modest means could easily get this project started.
For comparison, the commercial aquaponic unit, 24' X 60', $17,000, produces 1,000 pounds of fish per year, plus 8,500 - 14,000 pounds of veggies (based on mono-crop, like lettuce). Certainly, this technology is more appropriate for larger projects. A medium-sized school would need to produce far more than 86 pounds of fish a month to provide protein, so you would need a lot of units to become self-sufficient. It would be expensive to set up. How intensive is the actual work? How many students would it take, per day to monitor, harvest, "feed" and clean the water? Some aquaponic systems are so sensitive that one day's lack of attention ruined a whole greehouse full of tomato plants. Are there sufficient safeguards for students to be able to manage it?
I think it is an excellent idea to spread the self-sufficiency concept by utilizing the schools!