I need help with facebook!!!?

Ok i created a group on facebook called Cl of 2015 for my school..i added all the kids in my grade and then i accidently removed myself! I rejoined the group and then once i did i was no longer the admin..there is no admin listed for the group and the kids in my grade are getting mad about the group and they are threatning me and stuff i need to know how i can get to be the admin again or just remove all the ppl in it so i am no longer being bullie plzz help