We start with a discussion on different forms of power that could be used for our cars once oil has run out and their advantages and disadvantages. We discuss the possible shapes for the buggy and then the pupils design their own Buggy which harnesses the energy from an inflated balloon. Using just the materials they have been given they individually use their measuring and making skills to construct their buggy. The pupils keep the buggy they have made. If there is time we have a race to find the buggy that travels the furthest in a straight line. Shell developed the basic activity; my variation is that each student uses their full design and creativity skills for the chassis, so you get all sorts of different shaped buggies.