This California (where else?) school and its PTA put together a great, comprehensive all-school event around the environment and healthy habits and fun.   Check out their Eco-Extravaganza here. 

Especially neat, in my opinion, because these guys really went all-out.  Goes with a column I wrote a year or two back saying Go Big or Don't Go at All.  Basically, I think PTOs and PTAs do far better when they do fewer things in a big way than a lot of things in a so-so way. You agree?