One of the things our kids did was Riekes Nature Studies[1] which gave them one day a week where they spent in a variety of activities with other kids in a large park nearby (Huddart Park in Woodside). This became one of their favorite things to do because not only were many friends present, the facilitators were excellent at engaging the interests in a wide variety of kids. I remember "forcing" my youngest daughter to go and once she went she couldn't stop talking about how great it was and developed many friends that persist to today.

As a parent I came to realize that kids are unlikely to try new things spontaneously if they already have an activity they could be doing which meets their expectations of interest. So as a parent it was incumbent on me to give them the exposure to new experiences in order for them to develop their own understanding of what they did and didn't like.

[1] http://www.riekes.org/nature/