My friend is being abused. please help?

okay so i have this friend(no it really is friend not saying any names just in case someone i know reads this…)anyways i have this friend and her boyfriend is abuseing her all the teachers at school know he does it…but i dont think theres really anything they can do about it because he never hits her at school just verbal abuse…but i’ve seen bruises on her…over her on her arms….he used to date my cousin so i know he abuse’s her…his hit both of my cousin’s (girls)and my other cousin(boy)and when i was talking to her about it in the hallway about how she doesnt need to take that from him she said i know and as i was about to leave for cheer practice i saw a bump over her eye and i asked her did he give this to you..and she just looked at the floor…i told her she didnt need to take that from him and anyways some time passed maybe a couple of mintues and her boyfriend showed up and i start yelling at him saying he doesnt need to hit her he said “i’ve never hit her” to which i reply ” oh come on we both know that anit true ” and he said “man whatever i’ve never hit her you’ve already got your family thinking i beat your cousin(the one he was dating just to clear things up)” anyways he got mad and grabed my wrist and i said just ” okay grab me if you want too just remember i hit back” and his girl friend jumped in and was like “it’s okay we’re just gunna leave” and she walked away with him…...but thats not the piont i wanna get her out because now shes pregeant with his kid and i dont want him abuseing her anymore….he was yelling at her today after school and knocked her books otta her hands and walked off and as soon as she picked up her stuff and walked away he started to follow her and yell….well after awhile the teacher got into their arguement and made him stop and she went home…...................everyone knows he does this…..I NEED HELP WHO DO I TELL TO MAKE THIS STOP ! WHO DO I TALK TO PLEASE BEFORE SOMETHING HORRIBLE HAPPENS….PLEASE HELP ME I DONT KNOW WHERE ESLE TO GO OR WHO ELSE TO SPEAK TOO…