Now, if you foster a love of drawing and general mark-making in your kids, well, they're gonna draw. A lot. On things.
This does not have to mean you must create a vast wasteland of used up paper and dead trees.
We all know about the problem of drawing on furniture and walls and other non-drawing surfaces. For this I advocate lots of washable markers. And in nice weather, chalk for outside. Our son tried to convert his room into outer space by drawing space ships and planets on his walls and door. It was pretty clever. We took pictures of it before trying to wash it off. We tried not to admire it too much in front of him, though. I was very stern and all that.
Then, there's paper. We all know that we should be recycling, and re-using the backs of things is great. Cardboard from packaging is really nice. Let em make marks, then recycle the whole kit-and-caboodle. Let em color the funnies. If you like something, take a picture of it first. Or, use it to make a greeting card to send to the grandparents.
But if you really want to be environment-savvy, get your kids a white board or a chalk board. A big one for their wall, or a small one to carry around. Both are great because they are tactile, and you can draw by erasing too. MagnaDoodles are okay, but not as easy to use. And the magnet stuff starts sticking when it shouldn't after about the zillionth drawing.
The impermanence of a white board or chalk board I think is healthy, too. It tells kids that the act of drawing is what's important, and you don't have to frame everything in order for it to be valuable. And, a drawing can evolve - get partially erased, get mutated, whatever. It's a living thing.
Oh, and if your kid draws on the white board with a permanent marker (yike, how did they get a permanent marker?! Probably the same way they do at my house -- I have no idea), just do this: Go over it with a white board marker, then erase. I learned that in corporate-land.
There. Drawing does not have to mean wasting paper. Isn't that great?