Part of my philosophy in raising successful teenagers is to keep them busy. Kids this age get bored easily and a bored kid is much more likely to get into trouble. My boys don't care for sports and don't have boatloads of friends, so the activities they do as volunteers help keep them on the right path.
I also love to see them focused on helping other people. Teens are the most self-centered people in the universe. I'm not sure they ever even SEE anyone else on a normal day. But when they spend a week working on an Indian reservation or cleaning up flood damage in New Orleans, it gives them a whole different view of the world. They not only learn that they have it pretty cushy (despite their constant whining about chores!) compared to other people in the world. But they also learn that they have the power to make a difference.
I love for them to see the look on people's faces after they've helped them. Usually people are so appreciative when kids like that come to help them out. They understand that our kids are giving up vacation time and other fun activities to work on their behalf and they really let them know it. It's probably as close as a kid that age can come to feeling like a hero.
It also helps their positive self-image. This year, my younger son received a donation from the Mayor's fund towards his field trip, and merit badges in part due to his volunteer work. That makes him feel important. Doesn't look bad on a college application either. And I often hear my boys casually dropping their experiences into conversation with their friends.
It's also a wonderful way for them to spend time with other like-minded teens and supportive adult leaders. My boys usually do their work through an organization like Scouts or their church youth groups, but there are tons of other ways they can get involved through school or even just going around the neighborhood and offering to help elderly neighbors.
I'm hoping it will pay off in the long run. Maybe one day when they have their own children, I hope they will carry this tradition forward. I'd love for my grandkids to have same types of volunteer experiences as my sons have.