Re: recipe ideas for calcium
Green leafies are awesome sauteed in olive oil and garlic. Add red pepper and/or grated parmesan cheese if desired.
The more spinach-like ones also make an excellent spinach and tomato pasta sauce. (Eat as a vegetable side dish if you're avoiding pasta.)
Or throw a few handfuls into a stir fry, with either chopped up stems (like chard) or something like snow peas added for crunch.
They're almost all tasty raw, and can be used in both fresh and wilted salads.
I like them steamed with a splash of vinegar, but that's kind of an acquired taste.
Be sure to rinse thoroughly before cooking, as they do tend to come with a bit of sand. The books recommend using enough water so that they float and the sand settles out.