I wholeheartedly endorse this novel.
With the caveat that there are a few parts that are pretty darn difficult to read. This being a book about WWII, the Germans vs. the Russians, the siege of St. Petersburg, and a whole lot of hunger, it's not too surprising that there are sections that detail how horrible human beings can be, especially brainwashed human beings. (Or evil at heart. I cannot decide, in the end.)
The remainder of my endorsement is valid because while you wince and cry and gnash your teeth at the horrors of war, a page later you are actually laughing at the interaction between these two very, very different youths. And loving how their differences are championed by the author. I mean, if this isn't a showcase for diversity, I don't know what is.
And it's another of those books that has a well-considered last line, and I do always love well-considered last lines (and the plot structuring that goes with it).