If you are looking for a light yet non-frivolous read for a 11-15 year old, you should definitely consider this book. I ordered this one for my younger sis and she loved it. I myself liked the book a lot.
Although there were some goof-ups in the delivery by the courier partners of Flipkart, they did send a replacement. I have placed more orders since and Flipkart seems to be back to their normal, awesome self again.