What should i do!?

well, my friend is 13, and her stepmom abuses her. Her dad is aware but won't stop it. the school checks her out twice a week for anything new and they said if they find anything else that they will file a police report thing. she gets hit, kicked ect everyday, i guess the school just doesn't seem them? idk but, we were talking the other day about a lifetime movie where this abusive boyfriend killed his girlfriend cause she wanted to break up and at the end of the movie the judge said "anyone at that school could of prevented this from happening. everyone knew what was going on, but no one ever reported it." and it got me thinking if her step mom kills her, i would feel responsible. What should i do?