The den leader provides several pieces of rope or cord about three feet long. The den chief or helper asks a Cub Scout if he can tie an overhand knot in the middle of the cord without letting go of either end. He lets the Cub Scout try it, then he shows him the trick: First he folds his arms over his chest, then he leans over and picks up each end of the cord without unfolding his arms. As he straightens up, he unfolds his arms – still holding the ends of the cord – and, presto, there’s the overhand knot