I agree that your husband's living arrangement is inappropriate for a 16 year old girl. If I were you, I'd stop going to him for advice on how to handle the kids when they act out. You don't trust his judgment to make sound decisions right now, so why would you value his advice? If you aren't going to value his advice, why ask for it? Instead, I'd reach out to a counselor, a trusted clergy member or teacher/school administrator for advice. Also, if your husband is not dependable to help the kids out with homework, seek help from a tutor or teacher friend.
While it would be ideal that he be there to help you raise the kids in a loving, healthy, reasonable and responsible way, the reality is that he isn't right now. So once again, take him out of the equation and find a way to deal with these problems without his assistance. I KNOW you can do this! Reach out to your trusted friends for help when you need it. I have no doubt that you have many people who care dearly for you and your family and would love to help you in anyway they can.
I'm sorry the kids are struggling as a result of your husband's poor decisions. Just continue to be there for them best you can. While they may take out their anger and hurt on you now, I am confident that they will forever appreciate you being the rock they could depend on during this difficult time.