Greenhouse gardening

Quick post today...
I went with my dad to the Greenhouse gardening class at Thanksgiving point today. I went last year and had a great time. We planted lettuce, broccoli, cabbage, glacier tomatoes, spinach and swiss chard. I'll post pictures next week when they have sprouted. Did you know most garden veggies like 75 degree soil for germination? So my brain is thinking of ways to make my own greenhouse and make it one that the rabbits can live in so it would have to be heated during the winter and cooled during the summer. I've also been thinking about trying to find someway to get the kids involved in a micro-business. Worms promised to be that business for me as a kid, but they always died. My wife also sold worms from her backyard as a kid. So I've been doing some research and I think I may have struck on a plausible business plan.
Step 1: Clean out the shed, insulate the walls, properly arrange the stuff thats in it to give us one free wall. Install electicity to the shed and hook up an air conditioner/heater unit ( we already have a window unit in the garage).
Step 2: Move the rabbits into the newly thermally controlled shed.
Step 3: Buy/Make a worm bucket farm
Step 4: Buy red wigglers and start the worm farm
Step 5: Start seeds in the shed, grow them in garden.
Step 6: Sell worms to pay the electricty bill for the shed/greenhouse combo

It is pure genius I tell ya... The rabbit pellets and garden waste feed the worms. The worm sales pay for the electricity in the shed/greenhouse. And I get all the 'free' plants I want from my shed/greenhouse. This should be a self-sustaining system and that makes me happy!