Show students the circuit set-up and ask them why the light doesn't come on. Accept all answers that refer to an incomplete circuit. The teacher selects an item from the mystery box and demonstrates how to complete the circuit. Have students select an item from the mystery box and attempt to complete the circuit by making the item touch both paper clips. Have students identify common properties of those items that make the lights come on.
Metals are conductors of electricity.
When the circuit is incomplete, the path of electricity is interrupted. Meets objective D. Students will work in groups of four. Take two lemons and the LCD chemical clock and place each a copper and zinc end of the LCD chemical clock into one lemon and do the same with the other lemon so that the time display comes on on the clock. Discuss with students chemical, solar, and mechanical energy and their uses. Performance or authentic assessment is used for this topic.