Get a tennis ball or small, soft ball and collect a set of 6 quart-sized plastic water bottles. Fill the bottles partially with water and put on the lids. Place the bottles in a triangular pattern as for bowling. Make a line 10 to 15 feet in front of the bottles. This is the foul line. Take turns trying to knock down the bottles by rolling the ball. Each person gets two turns to try to knock down all six bottles. Keep score for 10 frames and see who wins!