There are several games online to teach people about sustainable living, “My Sust Home” however has the advantage of being presented with a a pair of charming Scottish accented narrators. Not only that but the interface is pretty slick, and the tips they give you are very informative without being overbearing.
I would highly suggest giving it a try. Not only will you have fun, learn about sustainable living, but as we all know everything is better with a Scottish accent. (also see if you can spot the Loch Ness monster, a strong proponent of solar power, or so I hear)