This is a fairly comprehensive, almost time-line like, look at the Holocaust for younger people. It should be noted that there are a few pictures that aren't really what one might want their children to see. Mass graves with bodies visible for example. An execution getting ready to happen for another. These pictures are commonly found in other books relating to this period though so while they aren't uncommon they can still be frightening for a preteen/teen. They're frightening for me, as an adult who has seen many such photos in my time reading and learning about the Holocaust.
Even someone well read may find a new tidbit or two about something they had read generally about before. There are plenty of pictures are actual people, Nazi's and others, photos of documents, etc.
I personally don't prefer my books formatted like this. There are little blocks throughout, mixed up, telling you a little about this person and this point, a little about that person at that point.
While it works it's just not for me. I can see how a younger person may like the formatting more than something more memoir-like. Overall it seems to be a good book on the subject for the target group and thorough.