Good luck with the reading program. I don't get the schools saying you can't read lower Lexile books - by 8th grade middle kid was at a graduate school Lexile level, so I don't know what she would have read if the school had limited her. There are plenty of HS/college level books that are worth reading and discussing.

Hopefully she likes LOTR. DH loved these, but middle kid and I could not slog through them. Both middle kid and I have read a lot more books than DH, and we both have read a wide variety of books, but just couldn't manage LOTR. I think you love it or you don't.