Primarily geared towards IB Biology, but this website is incredible. There are great links down the right side of his page. If you mouse over the options tab you'll see Option G: Ecology & Conservation. He's got a ton of excellent resources there.
I would not have survived teaching IB Biology without his stuff.
The first embedded document is the summary of an ecological footprint assessment my 7th grade students a few years back.
There is also lots of IB Biology resources (mostly from Steven Taylor at i-biology.net)