Logan, Candy, and some of the other Pettalkers have given you great advice. I haven't personal experience with kids of that age but, because of something terrible that happened to a 13 year-old girl in Connecticut this week, I would like to add this: Keep an eye on her when she is in the Internet or talk to her about the dangers of communicating with sleazy or dangerous people in chat rooms. I know this will be difficult without encroaching in her "space." However, if you can prevent a tragedy, it will be worth it. Sorry to bring up this subject, I was very shaken by the story of this girl and thought it was appropriate to tell you about it.
Tonya had the right idea about having your niece do something with or for animals. As a friend of mine says: give a girl a horse and you'll never have to worry about her being in bad company.
Good luck!!!
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