If you enjoy history, I recommend Civil War reenacting. I started in January and am having a great time. It is a hobby any age and gender can enjoy. We have guys & gals, ages 9 through the early 70s. You can be artillery, infantry, dismounted cavalry, cavalry, civilian, medical, etc. If you enjoy making things, you can be a sutler and sell your products to the reenactors. Teenagers, both male and female, can be soldiers and it will be historically acurrate. Many females did pretend to be males so that they could fight in the war.
If you are in Texas, here are two links to check out:
http://groups.yahoo.com/group/CivilWarTXunits/
http://www.11texascav.org/
I hope this helps!