From a story on WKBT:

Students at Onalaska High School will get the chance to see their carbon footprint. Onalaska High School was awarded a “Focus on Energy in Wisconsin” grant.

Teachers were able to buy six digital thermometers and energy watt meters with the grant money. The digital thermometers measure energy efficiency, for example, they can be used to test for air leaks around windows.

And the energy watt meters can be plugged into an appliance or gadget, like an iPod or a cell phone, to show how much electricity that appliance is using.