A thought provoking read, covering difficult topics such as Fascism and conspiracy theories. I enjoyed it, and was gripped, but it was also disturbing. Although ostensibly a children's book, there are some scenes that are brutal and violent, and also some swearing, so I wouldn't recommend it for younger readers. It would make an interesting read alongside The Diary of Anne Frank (if they still study it in school!) for a more mature reader.
I would always recommend parents read along when children are attempting books like this so you can all discuss the difficult topics when they arise.