The science project catapult kit allows you to tinker with the design of a medieval siege weapon, and provides you with the information needed to analyse your results. The catapult can be changed from a wheeled, sling type trebuchet, to a bucking spoon-arm onager in minutes. Power the siege engine with a free-swinging counterweight or fixed rubber bands. Vary the counterweight mass, projectile mass, or sling length. Install the optional crash bar or let the arm swing free. Compare the results of all the different configurations, and draw your own conclusions about which design is the ultimate medieval artillery weapon.