I am so amazed at some of these responses. Yeah, let the kid go. They are dispensable. You don't need to see them every weekend. ?????
If he is on the birth certificate, she will have some explaining to do with the judge whether they have a court order or not. Courts do not look favorably on parents who move their kids. I am one that moved my kids (but brought them back). We had to go to court. My ex was not paying support at the time and it didn't matter. They look more on the parental relationship. I will also say, the very first question the new school asked me was, where was my court order allowing the child to come into a new state. If this new school does not ask this, then the mother is probably not being truthful who the real father is. He has rights to know the school, to get paperwork/grades from the school etc.
Sorry to say, but jobs do not trump all when it comes to family court. The best interest of the child trumps the courts. If your nephew does not have the funds, perhaps you have a legal aid or we have a law college that works for low income. If he is on the birth certificate and she has nothing in writing allowing the move out of state, the father can contact the school and the school has the authority to notify the authorities. If he's not on the birth certificate, extremely harder and would require paternity testing. The other option is for him to file for visitation and to make sure she has to pay for all travel expenses.
Just read a few more posts while I was writing: Whether someone has a custody arrangement or paying child support, if someone is listed on the birth certificate, the other parent must get permission from the courts (if the non moving parent contests it). I'm also baffled that a 14 year old should know what's appropriate when making a big move like this. Like I said, I would be extremely surprised if the new school does not ask for paperwork. Been there, done that.