I think having friend(s) to go with is very important. I think my kids got lucky. They knew this kid in school whose parents are busy working and spends most of his after school time with grand parents and siblings. In other words, he's pretty much free to do whatever he wants. He's the kid that invited and introduced my kids to taking the bus to the mall and spend after school hours just chilling at the mall. He's also my son's biking buddy and showed him around the neighborhood plus much more on their bikes.

Yea, I think it's great to encourage your kids to go out for their own adventures. They will probably enjoy it a lot and have a great time.