MARBLE MACHINE ACTIVITY

Things you'll need to do this activity:

Step 1: Gather your supplies - many of which are recycled materials you can find around your house or classroom.
→ Pegboard - we use a piece 2 feet by 4 feet, but you can choose any size you like.
→ Ramps, Tubes & Funnels - we use things like wrapping paper tubes, thin pieces of wood, plastic tubing, old soda bottles, tin cans, film canisters, funnels, PVC piping - Get creative!!
→ Pipe Cleaners, Wooden dowels and glue gun - These are used to attach objects to your pegboard. Use the pipe cleaners to wrap around an object, then tie in the back (shown in step 1) or glue dowels onto your objects to stick into the pegboard (also shown below).
→ Marble - this can be any size or material you want, however, if you want to make a sensor out of copper and wires, the marble will have to be metal.

Step 2: Start building your marble run. We'll start by adding a funnel to the top (start) of our run. (1) Use a paper punch to put two holes in the funnel. (2) Thread a pipe cleaner through the holes in the funnel and then (3) through two holes in the pegboard. (4) Twist the pipe cleaner together to secure in place. What else could you use to attach the funnel? Try using something else at the start of your run.

Step 3: Add more ramps, tubes, and funnels. Here we used wooden dowels and hot glue to make supports for our tube. Make sure you measure and mark off where you want to attach your ramps to the board first - or your pegs might not match up! Another good practice is to test with the marble each time you add something to the pegboard.

Step 4: Here's what our marble machine looks like so far - we've attached things both with pipe cleaners and wooden dowels.

Step 5: Now that you can make our marble move through a machine using gravity - let's add a sensor and make something happen when the ball hits the sensor. In this example we're going to create an open-ended electrical circuit that is completed with the metal marble, turning on a small light.

Supplies you need to build a sensor and turn on a small light:

Step 6: We're going to create an incomplete electrical circuit using the above supplies (if you don't have alligator clips paper clips work, too). The circuit will be completed when the metal ball rolls in between the copper strips. Let's start by adding the copper strips to a ramp. Fold one piece of on either side of the end of the ramp, and secure with tape or hot glue. Make sure that they do not touch one another, but that they are close enough to allow your metal marble to touch both as it passes over them. On the underside of the ramp attach the alligator clips (or paper clips) to the ends of the copper strips. Again, make sure that they do not touch.

Step 7: Now at the ends of the alligator clips you'll want to attach the telephone wire, a AA battery, and the light to the ends of the alligator clips. The whole thing will end up being connected in a circle - open only where the copper pieces are. Start by stripping the plastic coating off the tips of the wires. We're using a wire-stripping tool, but scissors can also work (be careful not to cut through the copper wires). Depending on the length of wire from the alligator clips, you may want to add more wire (wire from an old Christmas light set works great).

Step 8: Let's give our light some power by adding a battery onto one end of the alligator clips. Tape the end of the wire onto either end of the battery.

Now take a new piece of wire, strip both ends, and attach one end to the opposite end of the battery - this wire will connect the battery to the light.

Step 9: Now let's add a light to the opposite end of the wire coming from the battery. A christmas bulb light works great. Now test your work by touching the two copper pieces together - the light bulb should illuminate!

Step 10: Now it's time to attach everything to the marble machine! We used a small piece of plastic formica and a wooden rod to act as a little shelf for the battery to sit on, and then just taped the light bulb above the ramp with the sensor on the end. But you can do it however you like!

Step 11: Here's what your sensor and light should look like when the marble rolls between the two copper pieces.

Step 12: Here's a look at the ramp with the sensors and the metal ball completing the circuit - since this is the "end" of out marble run we turned up the corners on the copper pieces to stop the ball and ensure a completed circuit.

Step 13: Here's an example of another way to attach the sensor apparatus - this will allow the ball to continue on down the ramp after it triggers the sensor. Note: the two copper pieces are bent so they nearly touch each other - allowing the ball to slow a little and have time to complete the circuit.

OTHER THINGS TO TRY:

→ Make your machine extend off the board, onto the floor and off the sides.

→ Try attaching a motor to the sensor apparatus and make a fan (or something else) spin around. Note: Make sure that you are use a low voltage motor (1.5 volts).

→ Add decorations or cool pictures to your machine - make it into a pice of moving art!!