This game is ideally played with a volley ball net and a beach ball. If you don’t have those, a rope tied at volley ball net height and a balloon will do.
All the girls stand on one side of the net. One girl hits the ball up into the air. She then goes to the other side of the net. As the ball comes down, another girl hits it up before it hits the ground. The second game follows the first girl to the other side of the net. This continues until there is just one girl left on the starting side of the net. She knocks the ball over the net and then play starts again. Order does not matter but the girls may find the game is more successful if they pick a girl who is good at volley ball to anchor each side.