My sons leg was broken by another student

My son was playing soccer during P.E. another student was kicking everyone. He said she always does that during soccer. I also spoke with two students who said she does it to everyone. She kicked him once, and he started limping. She kicked him again, and he went down. I was in the car line at the school when it was happening. Three teachers came to get me and told me he was hurt, and they called the ambulance. He was still lying in the dirt, screaming in excruciating pain, when I got to him. In the ambulance, they gave him fentanyl; when we arrived at the hospital, they gave him morphine. He wouldn't let them look at his leg; he was scared to move it. They put him to sleep, cast it x-ray, and cleaned him up. The x-ray shows his tibia is broken, and he may require a metal plate. He has an appointment with a pediatric orthopedic surgeon. I want the school to pay for his medical bills if possible. This has been very stressful he still won't try his crutches he is scared to stand.