What are the best parts about being a writer for young adults and teens?

Hi Samantha, I love writing too. Although I don't do that for a living I'd say the best part is that you can be happy.
There is always going to be young adults and teens so the audience is definitely a good target but if I can give you an advice don't stress over the audience, focus on writing the best you can.
The second piece of advice I'd give you is do not lose confidence if you don't get to publish your work.
I found myself in that situation years ago and I got very upset for a while.
You write because you have something to say and this is great.
You write because it makes you happy and nobody can put a price on it.
Wish you great flow of thoughts.

Samantha, writing for young adults and teens is very self-satisfying. There is no greater feeling than having a young person say that your writing has spoken to them or made them laugh or wanting to be friends with your characters. If writing is your passion, then you must write. Doesn't matter is you ever sell a story or not. Fantasy is a great way to break into young adult/teen writing. It's a very popular genre. Before you try and share your story, make sure you get it edited. Have a friend read it, or a teacher or a librarian or another writer. Remember as a writer, your first draft is always going to need revisions. That doesn't mean it isn't good, it just means it can always be better. I always have at least five revisions for a short story. My advice to you would be to find and join a children's writing group in your area. The best group is SCBWI (Society of Children's Book Writers and Illustrators). http://www.scbwi.org/ They have regional chapters everywhere. Best of luck to you and never give up on your dream!