An activity that works for all ages, with only a few adjustments. Wheels and axles are one of the six simple machines that Renaissance scholars identified studying Greek technology. Complex machines, like cars, are built up of simple machines and other technology to make stuff happen. In this case, our cars take two (or more) wheels and axles, and roll down an inclined plane to get their kinetic energy.
Then again, the kids are mostly just interested in making a car that works, so all the technical fun science stuff can just be slipped in while you show them how to build their first car.
For preschoolers, remember that this is a challenging fine motor skill activity, and while they might need help, let them lead as much as possible. The 8+ kids in my class had very little interest in following along, as usual, so they actually took longer than anyone to figure out how to make this work, but by studying a sample car they eventually all got there on more or less their own.
- toothpicks/round sticks
- cardboard, cut into strips (we used egg containers, which gave a lot of variation)
- any other stuff you dream up.
Each car calls for two toothpicks, and two segments of straw cut a bit shorter than the toothpicks.
- Tape the straw segments to your cardboard strip. This will hold your axle-wheel combo.
- Insert one toothpick into each straw.
- Divide modelling clay into four and roll into balls or wheels, depending on motor skills/desired result.
- Attach wheels to toothpick axle, being careful not to stick it to the straws as well.
- Shape body of the car -- in our case, we folded our longer pieces into car shapes. This is also where a huge amount of invention happened.
- Test on an inclined plane. We used a table leaned on a chair.