I would have suffered away from home as a kid so my schoolwork wouldn't have been good. My older sister (hearing) would have loved being away from our family. She loves us, but is independent and hated the busyness and energy (7 people, dogs, cats, and from me: rabbits, hamsters, birds, snake!

). Every kid is different. For some, being away is cruel, not helpful.
Have you met with her teachers and school counselors about her problem? They have the experience and maybe can tell you if she is better at home or at school.
Poor girl. And poor mom for a tough spot!