Clown Bowling
Fill 10 two-liter bottles with 3.5 to 7 ounces of sand or water, depending on the skills of the players. For more skilled players, more sand or water is appropriate. Push a Styrofoam ball onto the top of each bottle mouth for a clown head. Make clown faces on the balls. Glue pieces of yarn on the ball for hair and draw a nose and mouth with a marker or glue on pieces of felt or pom-poms. Set up the clown pins in pyramid fashion and let players bowl a tennis ball or other lightweight ball into the pins to knock them down. Give prizes for players who make a strike or keep track of points and name a winning team.
Table Top Bowling
Place empty yogurt containers at the end of a table in a triangular configuration such as five in the front, four in the next row, three in the next row, two after that and one in the very back row. Instruct players to blow through a drinking straw at a ping-pong ball to push it down the table and knock down the empty yogurt containers. Players need to be in close proximity to the "pins" in order to knock any over.
Big Ball Bowling
Big Ball Bowling is like traditional bowling but you use 10 two-liter soda bottles filled partially with sand or water (anywhere from 3.5 to 7 ounces of sand or water per bottle is a good amount) as pins and a large activity ball as your bowling ball. Fashion a bowling alley on a flat, smooth surface and place the 10 pins at the end of the alley in triangular configuration. Place the pins close enough together so that if the ball hits in the middle of the pins, it will likely result in a strike. Give prizes for people who knock all of the pins down or keep score and give a prize to the winner.