He most likely will not be able to register for school if the state he is in has registration requirements similar to NC - uless he somehow becomes emancipated. Also, there is no state where a 16 year old or even a 17 year old can hang out and give the custodial parent the finger and not be made to come home - again unless the child is emancipated. Not sure where you got that info from but it is flat wrong. Basically, he won't be able to choose where he wants to be until he is 18. His best bet is to hope the adoptive father doesn't find him but if he does, adoptive father has the right to snatch him up by his ear, throw him in a car and biddy bop back to the 'ol homestead.