Dit Dit Dash
Brevity = Soul of wit etc.


Circuit Quiz Game:
Simple project to teach kids about circuitry
by Ben Wheeler
MAKE Magazine vol. 05 p. 129
2005

Arthur C. Clarke's third law states that "any sufficiently advanced technology is indistinguishable from magic." Clarke's law could use a corollary: it doesn't take much to be advanced enough to seem mystical. In fact, advanced tech doesn't impress today's kids, who are used to every teddy bear and softball being Turing-complete. To dazzle them you need older technologies like circuitry, which feel magical by their very simplicity.

Here is a simple project to introduce kids to circuitry. It is a quiz game, where a light bulb signals that the correct answer has been selected. The circuit itself is very simple, but with enough different sections that it's surprising and satisfying to see it work. The questions can be quickly swapped in and out and rearranged, making for fast competition, impromptu topics and ridiculing siblings.

Matching questions and answers are attached to a board by paper clips, which are connected by hidden wires. A light on the board and a battery behind it are hooked up to two wires that dangle on the front of the board. By touching one wire to a question and the other to its matching answer, the circuit completes across the hidden wire behind the board and the bulb lights.

Circuitry projects are also a great opportunity to teach a child circuit diagrams and show how the path of electricity maps from symbols to reality.

This circuit diagram isn't necessary to build the actual quiz circuit, but once finished it is useful to refer back and see which of the diagram's cryptic symbols have become clear.


All of the circuit components are available at Radio Shack stores or radioshack.com. A few local hardware stores still carry such things, but nowadays even Home Depot doesn't stock them.

You only need a few special materials.


Time: 30 minutes

Materials:
  • 6-volt light bulb (Radio Shack catalog #272-1128)
  • light bulb base with screw terminals (Radio Shack catalog #272-357)
  • 6-volt lantern battery (Radio Shack catalog #23-016)
  • wire spool: 20-gauge, insulated (Radio Shack catalog #278-1225)
  • duct tape
total cost: $15

Making the base to support the quiz as it stands up, and house the battery


1. Make the board

Use two large pieces of cardboard, one for the quiz board and one for its stand. To form the stand, cut out two identical trapezoids, about 6" on the top and 9" on the bottom, with sloping sides. Tape them together along one side and to the bottom of the quiz board to form a truncated pyramid.

Wiring the light. Note that this shows the BACK of the board.


2. Install the light

Cut a small circle from the quiz board to hold the light bulb base. Also cut two amall slits on either side of the circle. Attach two wires to the light base (you'll have to strip the insulation from the ends of all the wires you use). Send one wire through a slit to the front of the quiz. Screw in a bulb and fit the base into the circular hole.

3. Install the battery

Put the battery inside the quiz stand. Attach the second wire from the bulb to the battery's negative terminal. Connect a long wire from the positive terminal through the other slit to the front of the quiz.

Wiring setup. For clarity, only one set of question-answer pairs is shown here.


4. Wire the answers

Make each question-answer wire by wrapping both ends of a wire around paper clips (make sure the connections are snug). Attach the clips randomly on alternate sides of the back of the quiz board.

5. Label the quiz

Make paper labels for the quiz questions and answers and place them under corresponding paper clips.

The finished product in action


Ben Wheeler is a math teacher living in Brooklyn, NY. wheeler.benjamin@gmail.com>