Princess of Glass, the 2nd book in the Princesses of Westfalin series, is just as wonderful as the first book. I loved it! It is full of mystery, adventure, and romance. Who could ask for more? It was very well written, a real page turner. Supposedly it is based on the fairy tale Cinderella, but it has such an incredible twist, its completely unique.
Just like with Princess of the Midnight Ball I would LOVE to rate this book G but unfortunately I have to rate it PG because again it has some scary parts in it. I would probably suggest it to 11 year olds at the youngest, and again anyone older than that can totally enjoy it too.
Here's a good summary.
http://en.wikipedia.org/wiki/Princess_of_Glass