I am always concerned when a teen has a negative attitude about going to school and wishes only to leave as a better choice.
If she were my daughter I would do the following:
1- Consider a physical examination to determine if there are underlying physical reasons for her decision to leave school. Teen depression can be one reason for a girl her age to decide to leave.
2- I would ask the following if she was my daughter: Talk to the school counselors with her present. Is there bullying in her school directed towards? Is she feeling anxious or overly concerned about someone or something? Does she want to talk privately with a psychologist in the school? Does she feel like school is too hard? Does she have difficulty with organizing her thoughts? Hard time getting started working and then feels that she is not accomplishing her work up to teacher standards. These and many more questions about her day to day life in school may shed some light as to what is her reasons for school refusal.
Here are also some links to help you and your daughter: