Outline:

lay out an area with two distinctive ends (eg:trees). Pick two kids to be ‘sharkies’, the rest stand at one end and are ‘fishies’.  Sharkies say: fishy fishy fishy, come swim in our sea. Fishies say: sharky sharky sharky, you can’t catch me. And the fishies run to the other end without getting caught by the sharkies. If they are caught, they become (dancing) funky funky seaweed, which can’t move its feet but can catch the fishies. Winner is the last Fishy left.