General Review:
I read the William books as a child, and despite being an obnoxiously well behaved child, I still wanted to think of myself as an "Outlaw".

I would recommend them to anyone of such an age. I think they are genuinely improving. Certainly my memory of William, as of the Swallows and Amazons, provides a well buried counter to my natural inclination towards the effete.

William also provides a good lesson in free will, independent spirit and free thought. Which cannot hurt. (Unless you wanted to make an extreme reading of the William stories as a prop to the capitalist establishment...)

This Book:
This is an interesting exploration on the effect of the war on suburbia. You can read the War as a strong presence, or a background distraction. As a book pubished in 1939 it does not carry any sense of hindsight, it is a genuine account, maybe an escapist one, but genuine nonetheless.

William follows through the war in the next few books, I think I would suggest these as reading for anyone who wants an introduction to the impact of war, it is a more lighthearted approach than the Hitler Stole White Rabbit or even Anne Frank school. There is an honest evocation of the effect of the war on the Home Front, uncoloured by the historical perspective we have now.