Gingerbread Derby “On Ice”

To engineer your derby car, you first need to decide what materials you want to use.  Go on a scavenger hunt for edible treats that can work as your car’s base (a large flat item, such as a Graham Cracker), wheels, and end caps (such as mini marshmallows).  Make sure you also grab a straw and skewer.  Royal icing works well as your “glue” to hold everything together, but feel free to substitute white glue (just be sure you give yourself extra time for the white glue to dry).

Fun Fact:

Engineering is a creative process, where you ask, plan, imagine, create, experiment, and improve. A huge part of engineering is experimenting with different materials to figure out which one works best for your goal. Your goal here is to build a gingerbread derby car. Test out your materials and remember – if something doesn’t work, try something different in your quest to make a better car!

Axles are a rod that run through the middle of a wheel, connect the wheels to a car, and allow the wheels to spin.  To start creating your axles, place a bamboo skewer over the width of your car’s base.  You want the skewer to stick out on either side at least ¼ inch further than the edge of the base.  Cut or break the skewer to length.  Then repeat for your second set of wheels.

Tips & Tricks:

It can be hard to cut a bamboo skewer. Try asking an adult for help.

Cut 2 pieces of straw that are at least ½ inch shorter than your skewers.

Fun Fact:

If wheels were attached directly to a car, they wouldn’t roll.
Why? Because they wouldn’t be able to spin.
Axles are used to attach a wheel to a car, they allow the wheel to spin while the car remains straight, and they help make work easier by reducing friction. This is why together, wheels and axles are one of 6 simple machines! Can you name the other 5?

To assemble your axles, place a skewer inside each straw.  Then attach the straw to the base of your car, using tape or royal icing.

Tips & Tricks:

Tape doesn’t often like to stick to food. If you find your straw is falling off, try wrapping a thin strip of paper along the length of your car (covering the top and bottom of the base). Then tape the straws to the paper.

Push the wheels onto the skewers.  Some wheels will fall off if they don’t have an end cap to hold them in place.  If you need to, push end caps onto the outside of the skewers.

Make sure the skewer and wheels can spin without hitting the straw.

Tips & Tricks:

If you find the skewer and straw are too close in length, try cutting down the length of your straw.

You’ve built a basic car with a base and wheels – it should be able to roll down your ramp.  But, how well will it race?  Try adding a gummy bear “rider” and/or some other candy for added weight.

Tips & Tricks:

Engineering is all about trying things out to see if they will work.
Feel free to build your car however you want. If it doesn’t work the way you want it to, try modifying or even starting over!

Time to set-up your ramp.  Lean a flat baking sheet against a stack of books.  You can adjust the angle of your ramp by adding or taking away some books in your stack.

Racing is fun, but racing on ice is even more fun!  To make your ramp more like ice, place the trash bag or foil over the ramp and along the path you think the car will travel.

Fun Fact:

When your wheels roll down the ramp, a force called friction is slowing them down.
Smooth surfaces like ice have less friction than rough surfaces like sand or rock.
Because there is so little friction on ice, one push will make you travel further than if you were on a paved road.
But, there is so little friction on ice that you won’t be able to turn very easily!

Ready, steady, race!  How far did your car go?  Want to try again and see if you can get it to go farther, faster, or straighter?  Try making some modifications, or changes, to your car and try again!

Tips & Tricks:

Try adding more candy to the top of your car to add weight. What happens if you put the candy in the front of the car? In the middle? In the back? What other changes can you make?