How can you put your 17-year-old daughter in a boarding school?

Yes and no. You can enroll the "child" but if the child is as unruly as you say, they already are aware that they are old enough to be emancipated and drop out. I am curious what you hope to accomplish by doing this. If you are hoping to solve a behavior problem, it is simply too late. Unless it is something so serious that it requires a psychiatrist and medication, there is little you can do to change her. In a few months she will be a legal adult with all the rights and priveledges coming with it. If you are just having problems getting along and she is unruly, you are best to focus on your relationship and let her do her own thing. Keep a roof over her head and treat her as an adult. Allow her to do as she wishes as you would any other adult. I know it is tough, but at some point you are going to have to acknowledge the fact that she can move out, get pregnant, make you a grand parent, get married, and raise her own kids. She's not a kid any more. If you are unhappy about how she turned out, don;t worry, she will get older and wiser. The most important thing you can do now is actively work on improving your relationship with her while learning to deal with her in a way you are not accustomed - as an adult. If she steals, becomes physically abusive, or does things that are illegal, throw her out on her butt. She;s old eough to be emancipated. But don;t push her to that point by being overbearing and trying to control her. I can;t say when you lost control, but it's too late to get it back. All you have now is your relationship. Let the control go and focus on that.