I do this activity each year, as a introduction to electric current. It's
a discovery lab and ungraded. Once they see all four configurations, I ask
them what's on the inside of a bulb and a battery. Students have little
idea of the inner workings of everyday items. I pass around broken bulbs
and show that the electrical contacts on a bulb are separated by an
insulator. Batteries are more difficult to show, but you can show a lemon
battery (with a penny and nickel), etc. Students begin to appreciate and
understand these things. Unfortunately, few textbooks explain how things
are made or how they work.