Give fourth grade students some copper wire, a battery and a light bulb and challenge them to make that light bulb work. Do you think they can do it? Sure they can with some trial and error and perseverance they all can and did. After that they found it extremely easy to light two light bulbs, buzzers, and even a switch to turn the light on and off.
Using a model called Productive Talk which is simply a guideline for creating rich and powerful classroom discussions, the kids discussed, argued, and listened to each other about what will make a closed and open circuit. In fact later on the that night the kids were eager to share and teach their parents what they themselves discovered.