I have a catapult that is a class 1 lever i.e. a rubber band pulls down on the beem on one side of the fulcrum; the load is launched from the end of the beem on the other side of the fulcrum. I want to increase the throwing distance of the catapult. I recognize that one option is to increase the throwing arm - the length of the side with the load. According to the Law of the Lever, classical equation, I should also be able to shorten the rubber-band arm and see improvement. Now, I'm trying to explain this to 6th graders in terms of the Actual Mechanical Advantage and the Law of the Lever equation - and convince them that it really works that way. They intuitively want to LENGTHEN the rubber-band arm as they recognize that this would stretch the rubber band further and thus increase the force. Yes, it would increase the force, but it would reduce the mechanical advantage. But would it decreate the length of the throw? You see, now I've gotten myself confused too! 'Trying to use theory to support experience . . . What am I doing wrong?