Divide into two teams of 2 or 4 players. Each team lines up along the edge of the pool going different directions. We'll call the players for Team A, player1 and player2 and the players for team B, player 3 and player 4. Say "go!". Players 1 and 3 walk out in chest deep water about two or three feet and spread their legs. Players 2 and 4 then dive and swim between the legs of players 1 and 3 (2 goes under 1 while 4 goes under 3) and surface. Players 3 and 4 then spread their legs and their teammates swim under their legs. Players 1 and 2 continues to trade off while players 3 and 4 continue to trade off across the pool..