Spool Racers: Homemade Wind-Up Toy

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This post is one of my favorite things to make with my kids. It is a homemade wind-up toy and kids LOVE them! I have made these spool racers so many times over the years and realized recently that I have never posted about them!  What’s super cool about these is that they are a fun toy and a science lesson all in one.

What is a Spool Racer?

A spool racer is a cool homemade wind-up toy. They are made from a wooden spool, and they actually race across the floor or table.  It’s most fun to make a few of them and race each other to see whose is fastest!

How to Make a Spool Racer

You’ll need a few simple supplies:

Wooden Spools~ we painted ours just for fun  You can get these on Amazon, or save your old thread spools!
Rubber bands
Toothpicks
Masking tape
Metal washers

You start by threading a rubber band through the center of the spool.  It is tricky to get it through, so I usually grab the rubber band with a toothpick to pull it through. Don’t pull it ALL the way through, though!  Make sure to leave the end hanging out.

Break your toothpick in half to thirds depending on the size of your spool. Thread it through the end of the rubber band to keep it from pulling all the way through. Put a piece of masking tape on it to secure it.

On the other side, put the rubber band through a washer, then put a toothpick through the rubber band.

How To Make It Go

Wind up the rubber band and toothpick. You will need to wind it and spin it for a little while until the rubber band is tight and curled. The direction you wind it will determine the direction that the spool will go.  Test it a few times to figure that part out!

Once it is wound tight, just let it go and it will race across the floor or table!

What is the Science Behind This Project?

This is a perfect example of potential and kinetic energy.

Potential energy is stored energy. When you are winding up the rubber band, this is stored energy.  Once you release it, it becomes kinetic energy. Kinetic energy is the energy of motion. You can easily explain these two types of energy while making this wind up toy with the kids!

Make it more of an Engineering challenge by giving kids some variables.  Instead of the toothpick, use a pencil. Try different sizes of spools and rubber bands to see which works better. Try them on ramps vs. flat surfaces to see what works better.

See More Fun Homemade STEM Toys From My Site:

Shooting Star Spinner
Gravity Spinner Rocket
Homemade Catapult
Bubble Shooter
Cardboard Tube Rocket Blaster
Penny Spinners