A great book
Dawkins has written this book specifically for children in middle school though adults without a strong background in science could also befit from it. As a professor, author, lecturer, and promoter of science, reason, and critical thinking, Dawkins has written this book to help dispel all-too-common myths on the creation of the earth, what causes earthquakes, what rainbows are, evolution, and several other topics that that ancient texts have so clearly misunderstood.
Most chapters begin with creation myths for the topic discussed and it's not difficult to see how earlier fiction got so many things wrong with such a limited understanding of the natural world. The focus then shifts into how science, logic, and reason have helped us to better understand the topics. Each subject is explored in way that helps the reader to differentiate between the "old" understanding of myth and superstition and what we know now.
As an educator, Dawkins has thoroughly researched the topics but openly admits in a few places where he has reached the limit of his understanding as the material extends outside of his scope of knowledge. Instead of fabricating some explanation, he encourages the reader to further explore the topic to better their understanding.
Considering the intended audience, the author provides enough detail to covey a good understanding without getting too deep into each subject.
This is an excellent book for readers between 10 and 15.