I recently purchased a mini plastic bowling set for my girls for some fun indoor/outdoor play. My youngest is 14 months and oldest is 2. This is a great activity to practice coordination, balance, aim, crossing the body line, and gain arm strength. It's easy to set up, the concept is simple, and could be great for a rainy day as well. The girls love it and it only cost me $5 at Wal-Mart. Yay!There are lots of fun variations you can play as well: spinning/twirling and throwing, counting before rolling, tossing instead of rolling, using the opposite hand to roll/throw, etc.
Definitely worth the $5 around here! If you don't have them at your local Wal-Mart, Oriental Trading also offers them for $5.99.