What We Learned:
Sir Issac Newton discovered the principle that for every action there is an equal and opposite reaction. This is called his Third Law The water pours our of the small hole and its force pushes the carton in the opposite direction. This is what makes it turn. The more holes there are, the faster the carton turns.
This is similar to some turbines. Some turbines use water or steam that is forced a high speed through many small holes to turn a turbine around. The turbine is connected by a shaft to an electrical generator, which makes electricity when it is turned.