Be sure to check out https://www.STEM-Inventions.com/ for more projects like this!
Buy wheels: https://amzn.to/2rlipfl
Buy wood cubes: https://amzn.to/2C419ms
Glue gun: https://amzn.to/3nMFeDL

The Young Engineers series is a collection of STEM Projects that I developed while teaching K-6 students. Every project uses the same set of inexpensive materials so it's cost effective for parents and educators to do multiple projects or teach large groups. Printable lesson plans and project picture sheets are available at https://www.stem-inventions.com/lesso...

Slingshot Car:
The slingshot car is an excellent introductory project to illustrate how potential energy is converted into kinetic energy, and the importance of low friction. Just be sure to watch your feet as cars go racing across the floor!