For a 16 year old it's best to go to sleep at around 22:30 and to get up at around 7:30. This should allow her to be up in time for school and get about 9 hours sleep, which is what she needs.
If you are going to actually enforce a curfew on her, do it for weekday nights only. Leave the weekends to her.
If you are going to actually enforce a curfew on her, do it for weekday nights only. Leave the weekends to her.