So here is the "box" which is basically a 2x12x16 that I had them cut into 4 equal parts. Just used decking screws on the corners (3 I believe?)
I made 3 of them like Mel says to do, which is actually 12 squares in each. But one I made 9 squares so it was a little bigger for some things I knew I would need more room for.
Some of the things we grew were tomatoes, celery, squash, zucchini, strawberries, onions, peppers, broccoli, cauliflower, Kale (and a few I know I'm forgetting). And TONS of herbs! Which can be washed and frozen for all year round use. I blanched some of our veggies and froze them as well. LOTS of fun and good for you too!
And last but not least my little helpers who jump at any chance to drive the tractor! They are cute aren't they?