I wanted to include a few tips to help teachers with the buggy lab challenge.
One of the things that I made rather a big deal of, was figuring out how to make one of the buggies significantly slower than the other.
1) Grab some aluminum foil and some cardboard
2) Fold the cardboard roughly into the shape of a cylinder
3) Wrap the cardboard in the foil so that it is roughly the size and shape of a “C” battery
4) Replace one of the batteries with the foil cylinder and close the car.
You now have a nice slow car for buggy challenges!