When my parents moved to the states and I wanted to stay in school in Canada, they had to go through a lot of crap too. I lived with friends, and they had to get legal guardianship, so they had to get a letter notarized (my paretns are together and they both signed it so I guess that's why it worked for me). I also had to give the school ALL kinds of crazy ID.. my birth certificate, my drivers liscense, heath card, etc etc..

Anyway I ended up hating living with my friend because her mom was really awful to me - made me do her laundry and dishes, woulnd't let me stay out after 11:30pm on weekends; 5:30pm on school nights (I had a 3.98 GPA when I CAME to her house, and she said I was irresponsible.. b**ch ). So I left. Instead of telling the truth the about my situation the next time, I just went to the school and changed my address (to an office that was in the catchment - it wasnt even a real residence but I could bring in a hydro bill with the owners name on it so that made it legit.. I can't explain it ) and simply changed the name on my forms from my friends mom to my family friends that I was staying with. I guess what I am getting at is maybe you will have to "cheat the system" a little bit. I guess a concern is that her dad would spoil that for her, but to make a long story short, when we did it right we got screwed around. When we cheated a bit it was easy and painless I'm sorry it isn't working out for your niece.. I don't understand why her best interests aren't the primary concern of her Dad and new school