The 20 minute video with Annie Leonard tells about the implications of all the products we buy, and a little about why we buy them. I don't really think it says anything we don't know already, but it is good to get reminded every once in a while about where our "stuff" comes from and what happens with it after we're tired of it (unless you're the packrat type like us, who keep thinking that it will be useful someday and put it away in some safe place.
I think it would be an excellent way to illustrate the concepts to children, while reminding the rest of us who ought to understand it all that we should think twice before we accumulate more! The website has a wealth of resources as well to keep learning.
Here is the introduction to it, so you can get an idea:
There is also a banner for it in my banner collection on the right.