When I first started reading this novel it reminded me of the old Famous Five book by Enid Blyton that I devored growing up. These books consisted of a team of siblings and their strong-willed cousin and a dog that got into a variety of scrapes.
Saunders' novel starts in a similar way with a close knit family featuring children of various ages discovering a cute sand fairy called the Psammead. Psammead however is a being that has lived for millennia and as such has lived a very colorful life. In his present state however he is greatly diminished and is forced to reflect upon his previous exploits.
The novel is set in London at the start of the First World War and at first the childrens' lives continue as normal. Things change however and their older siblings find themselves involved in the war.
Saunders does a good job of showing how the children strived to find a sense of normalcy despite the chaos around them. The Psammead may very well have been an imaginary creature (no one but the kids could see him) but he served his purpose well.
Wars have been fought throughout history for various reasons, some fair and some not. More often than not it is the young who bear the brunt of it. Whether or not young people experience harm or not they bear some toll. I recommend this book for children in third grade and up. I think it is an excellent conversation starter and a great way to generate dialog about thorny issues.