Do I have any recourse against a private religious school that is kicking out my child for behaviors stemming from ADHD?

My child is diagnosed with ADHD, he has been in the school for seven years. In the beginning, he used to throw chairs and desks, he has thrown a hockey stick at a gym teacher, he has been physical with other children in the school. Over the years his behavior has improved but he still continues to have issues. He sees a therapist outside school once a week and twice a week in school. He is medicated and his has a full time shadow in school with him all day. Any time the school has asked us to do anything we have responded yes and have jumped through all of their hoops. They have requested a meeting with us tomorrow and we suspect they are going to kick him out of the school.