Both my 11 year old and my 6 year old were fascinated by this book. The book describes the size, feeding habits, migration habits and a bit about the young of this majestic mammal in accessible entertaining style. As always with her books the parents become better informed eg I did not know that there are TWO global populations of blue whales who never meet because when one lot are at the equator, the other lot are at the opposite pole to where the first lot have come from....prompted lots of talk about seasons change, the earth tilting etc The illustrations manage to convey the enormous SIZE of this gentle beast.This author is always entertaining and informative. I cannot praise this author and her work highly enough. This book inspired my kids and gripped them. . My kids were gripped by this book as by all her books. The language is easy enough for a six your old to read by themselves , perhaps with a bit of supervison or prompting. Really lovely book.