J.W.
I am currently doing a music class that my son loves. He's going to be one, but the classes are geared towards different ages of children. He's actually one of the youngest in the class and most are 1-2 years old. They have a breakdown of classes from infants to age 3, ages 2-4 and ages 4-5. So the classes are geared towards different ages and are in various locations depending on where you live. The website is www.sallysmusic.com
Another idea is a My Gym class, a MyGym just opened in Springfield and my cousin has her 2 yr old in a class and she absolutely loves it. Hope this helps, I have a son who will be 1 in June and I am always looking for different things to do, so thanx for asking this question, I'll be checking out responses to get some ideas. :)