I know these threads crop up all the time, but Mumsnet is great at this sort of thing.
I remember reading a book in English class at school, I was probably around 13 or 14 and it was a young adult type book.
The story was about a girl who had a physical disability and lived on a Scottish island. Her world was turned upside down when a wealthy American family bought the island, or all the farmland on the island, something like that. I remember that her disability affected her speech and she was trying to say her name and the American boy kept thinking she was saying 'Shoma'.
The only other thing I remember was that I think it was a male author, and that at the time I read the book I 'knew' the author because we had read other books by him in class. It would have been set in the present day, rather than being historical, but it's about 30 years ago now, so I suppose it's historical now 
Have been googling without any success and it's driving me mad.
Does it ring any bells?