From a very young age both of our kids practiced (violin and cello), took lessons, played in orchestras and chamber music groups, sang in chorus and in shows, and managed to become exposed to a lot of what I would consider worthwhile music through the stuff that they heard around the house.
I will never forget the day that my daughter Rachel (who is now 20) came into my bedroom and started singing some Simon and Garfunkel songs for me. She had just heard them on the radio (a few years ago "oldies" stations were all the local rage). She had a look of pure joy on her face while she sang them. She had found something of her own, and it was something really beautiful, and it was something she wanted to share with me. I loved Simon and Garfunkel as a teenager too. Imagine my inner kvell.
Our son Ben (who is now 18) and his sister share many of the same likes and dislikes in popular music, but Ben has been devoting a lot of energy into expanding his musical horizons backwards and sideways. The other day he took some recordings out of the library. They were recordings that were important in my husband Michael's teenage years, and if he had known Ben was interested in listening to them, he would have gladly let Ben borrow his copies. I was very happy that Michael was able to share that particular "discovery" moment with Ben.
As exciting as my own teenage musical awaking was, watching and listening to the musical awakenings of our kids is even more exciting. It seems that all discovery for a teenager is self-discovery, and that's one of the things that makes watching (and listening to) kids grow up so much fun.
Update! Ben just told me about his brand new myspace music page where you can listen to him singing (and playing guitar and cello on) some of his own songs.