Well, here's one for the books, so to say. A 10 volume history of WWI, written somewhere around 1920, by Sir Edward Parrott, for
children. It would appear that the children of the period had more fortitude than we'd expect today since the whole lot weighs in at more than 3500 pages! And, it's a free download from the
Internet Archive! It's apparently out of copyright so there shouldn't be any problems obtaining it. Total download is a little over 250Mb. Or, you could just read it online!
Hundreds of pictures, maps and drawings.
Here's the link to the main page.
http://www.archive.org/search.php?query=Children%27s%20Story%20of%20the%20WarEnjoy!