Paper Plate Pachinko

This playful musical maze uses a conductive marble to complete simple circuity connections on stacked paper plates that are hooked up to a Makey Makey device. The project highlights the importance of iterative design and problem solving. It can tie into NGSS Science Standards (PS2A: Forces and Motion and 4-PS3-4: Apply scientific ideas to design, test, and refine a device that converts energy from one form to another.) The project requires one to two hours, depending on the age of the participants.

MATERIALS:

Reusable materials:

• scissors
• hole puncher
• Makey Makey device
• computer with internet connection (able to use Makey Makey Piano app and Scratch)
• pliers (optional)
• wire strippers (optional)
• pencils marbles (one per participant)
• hot glue gun (optional)

Consumable Materials:

• sturdy paper plates with rims (two per participant)
• tape (clear or decorative)
• strips of colored construction paper
• electrical tape (optional)
• masking tape
• other maker materials like pom-poms and button
• glue gun sticks
• white glue (optional as this whole project can be done with just tape)

Conductive Consumable Materials:

• pipe cleaners (ends stripped of fuzz to expose half inch of wire)
• aluminum foil
• copper tape
• HVAC tape
• LED light (optional)
• 3V coin cell battery (optional)

Vocabulary:

friction, gravity, conductor, insulator, circuit, iterative design

Take two paper plates. Choose one to be the top plate. In this plate, cut curved tabs and push them downwards. (A hole puncher can be used to create a spot to fit scissor tip into to start the cut.)
Leave the bottom plate uncut.

Stack your plates. The tabs pushed downwards will keep the top plate elevated off of the bottom plate.

• In pencil, mark four spots on your top plate indicating where you want your marble to make a noise.

• From each marked spot, draw a line to the same location on the edge of the plate. This will be attached to your ground alligator clip.

Lay paths of conductive copper tape or HVAC tape along the lines you drew on the top plate. (tip: most copper tape is conductive only on the shiny, non-sticky side, so when you extend a conductive line, create a small folded over tab on the extension tape so that the shiny side of the new tape presses down and touches the shiny side of the previously laid copper tape.)

This is the fun part!

• Using thin strips of paper and other maker materials, create a maze on the top surface of your top plate. Test out the flow of the paths by placing the marble on the plate and rolling it along the surface as your rock the plate.
• Create little holding spots (such as cones of paper or coiled pipe cleaner baskets), where you wish the marble to complete the circuit (make a noise) at the X spots.
• There should be an area on the inside of each of these spaces that is conductive and attached to the ground line. Extend your conductive lines into these spaces by adding tin foil, wire, copper tape, etc. to your existing conductive ground lines.

• Connect an alligator clip to the edge of the top plate where the conductive lines meet.
• Attach the other end of the alligator clip into the ground strip of the Makey Makey.

• On the bottom plate, mark four corresponding X spots to the ones on the top plate.
• From each marked spot, draw a line to a different location on the edge of the plate.
• Choose a conductive material such as copper tape, HVAC tape (cut into thin strips), or pipe cleaners (with fuzz stripped from the ends). Using the conductive material, follow the path, for each line from the edge of the plate to the X marking. Leave extra material at the end with the X so that you may pull two to three inches of the conductive line through to the top surface of the top plate.

Attach alligator clips to the bottom plate where the conductive lines end at the edges. Attach the other end of each alligator clip to a different arrow key clip-ins on the Makey Makey device.

• Place the top plate on top of the bottom plate.
• Pull the conductive lines from the bottom plate to the top of the plate through the slots or create additional holes in the top plate.
• Use masking tape, blue painter’s tape or electrical tape, tape the top plate in place on top of the bottom plate.

• Making sure that the tabs of the top plate maintain a gap between the two plates.

Wrap your marble in copper tape or HVAC tape. Press tape down smoothly against the marble curvature so that the marble can roll easily.

• Complete the connections by placing the conductive lines pulled up from the bottom plate into the holding spots on the top plate. These conductive lines from the bottom should not touch the ground lines of the top plate, but should be close enough that when the marble rolls into these spots, it is a tight fit between the two conductive lines.
• Plug in your Makey Makey to your computer via its USB port and open up Makey Makey Piano.
• Roll your marble around on the top plate and into each pocket to test out that the connections. You should hear a different musical note when the marble falls into each of the pockets.

• Congratulations! You have a Paper Plate Pachiko game!

PROBLEM SOLVING:

• If you don’t hear a musical note when the ball drops into a pocket, re-position or add conductive materials to one of the circuity lines in the pocket to ensure that when the marble falls into the pocket, the connection is completed by the body of the marble.
• If you hear musical notes when the ball is not in the pocket, check that your hands are not touching the alligator clips as you hold the paper plates. Also check and make sure that the circuit lines are not touching inside the pockets. If they are, then you will hear a constant note.
  

• ADDING AN LED LIGHT: Real pachiko games have lots of lights in addition to sounds. You can add a light by using an LED light, a 3V coin cell battery and create an open circuit using some conductive material (copper tape or HVAC tape). To have the light illuminate when the ball rolls by, arrange the two conductive lines of the broken circuit close enough that when the marble rolls over it, the circuit is completed. In this sketch, the battery is taped to the underside of the top plate and the conductive lines and LED light are on the top surface.
• ADDING SCORING: You can create Scratch games that keep score and/or time the maze game play.
• SCHOOL CURRICULUM THEMES TO MAZES: Another extension exploration would be for students to create a second iteration of the device that reflects themes that they are studying in class. They could create Scratch games that share students recorded voices giving information about the curriculum subject when the ball falls into the pockets and triggers the circuit.