As a minor, you cannot move out of your mother's home without your custodial parent's consent (ie. your mother's permission). And if you leave without your mother's written permission, your grandparents could be charged with custodial interference. Not only that but you could be dragged back by the police. Your mother could also go in front of a judge and tell him that you are incorrigible and you could end up on juvenile detention.
Now what are your options...emancipation? You aren't likely to get it. What about your father? Would he file for custody of you? If he was willing to take you AND you told the judge you wanted to go to him AND he was a "fit" parent, then he could take custody of you. Or, you could examine why you want to move out. What is your mother's husband doing to you? If it is illegal, tell your teacher. Teachers have a legal duty to report abuse to the police and Child Protective Services..
Don't run away as that will get you in to further trouble. As for what you will find when you and your grandfather talk to a lawyer, don't get your hopes up. Parents have more rights than grandparents do. And a custodial parent in many jurisdictions can prevent a minor from having any contact with a grandparent if the parent (your mother) deems it necessary to enforce her parental rights. Instead, focus on what is going on in your home with your stepfather.
Good luck!
