Demonstrating how static electricity can help you roll an empty can of soda is a cool trick, but you can turn this brief and entertaining science experiment into a full fledged science project. The process can be kept the same but introduce some variables into the experiment and then make records of what happens with each variable.

Possible variables could include the size of the balloon, the length of  the person’s hair you charge the balloon on and even the amount of liquid inside the soda can. So here’s how you will structure your science project. Use two different sizes of balloons and see which one is able to roll the can faster.

A second variation will include using two volunteers with different lengths of hair to charge the balloon. Does the balloon get charged better with longer hair or with shorter hair? Try it out and then record the differences in your notebook.

The weight of the soda can may also be a major factor in the ability of the balloon to push it around. If it becomes too heavy the can will not be able to roll at all. So to check just how much water it takes for the can to not move you can measure out 10 ml water and add to the can and try the process again. The science project can have  many results based on the variables that you use.