You have a meeting with the school. So they know she could exit the doors at anytime without permission, so they will keep a close watch on her.
You then physically, as suggested, drag her ass out of bed, get her dressed.
Drive her to school, physically escort her into the office and release her to them.
You pick her up from school, having them detain her in the office until you can physically escort her out.
You take away every priviledge - no computer, no cell phone, no friends visiting. You put an alarm on her window and bedroom door.
Or...you call the cops to take her to Juvenile Detention.

