K.T.
Another option is that she is needing more sleep. I know that may seem strange, but when I've had teen foster kids, most of them benefited from an earlier bedtime (I'm talking 8pm for some!). Perhaps the "wind down" time is not enough. Just laying down at 9 doesn't mean any of us would fall asleep immediately. Take a look at her bedtime routine. Perhaps you and she need to make some adjustments there, too. I agree with the other poster: if she begins to have trouble waking at the appropriate time, adjust to an earlier time to bed. Good luck!