My 6 yr old was choked in class by another child. Is now in pain. Can I sue the school?

My child was choked with a blanket used during classroom activities. The offending child has hit my kid before. The teacher was aware of the issues with this other child and was to have been monitoring the situation. I only want to know how to safeguard myself if I end up having medical bills for my child as she is now in pain.