Where does our classroom's electricity come from?

Read this to the class:

A new student flicks on the classroom lights and asks, "Where does this actually come from?" Somebody says, "The wall." Somebody else says, "A power plant." A third person says, "In my old town it came from a river." Who is right? Your team's job: follow the electricity back to where it is made, and find out what our own province or state uses to make it.

Teams of three, with jobs that rotate halfway through: Lead (handles the cards and the device), Checker (reads sources and checks numbers), Recorder (writes and colours the chart).