This book is great for understanding differences between people around us. We may not look the same but may have common interests. I think this book would be good for any grade but for reading purposes it may be good for higher grades because of the language and how many words are on a page. I would use this in my classroom by giving the students a blank picture of the rainbow fish and they are to decorate it in anyway they feel. This will demonstrate that everyone is different and unique. The students could also write positive attributes about themselves that makes them unique. The Lexile Level is AD410L.