Hi Louise, I happened to see your question and since I have read some really good YA novels recently, thought I would give you some ideas. I have reviewed all three of these books on GR and Amazon:
I Am Wolf, by Joann H. Buchanan Jaguar Sun, by Martha Bourke Farsighted, by Emlyn Chand
I Am Wolf, by Joann H. Buchanan
Jaguar Sun, by Martha Bourke
Farsighted, by Emlyn Chand
Maybe one of them would be just right!
Best wishes, Fred