Personally, I like anything that deals with WWII. And this is on my list of most favorite movies set in the WWII years. This is perfect for anyone who likes a movie based on historical fact mixed with suspense and a terrific plot with diving depth, which, as CSM suggested, can open up a lot of good discussions.
There are things to watch out for, though. The violence is very realistic, as is the plot, and the effect will vary from kid to kid. The language isn't frequent but the sort you often find, sadly, in movies these days. Some of the messages could be misinterpreted by younger kids and would be good for them when they are old enough to decipher right from wrong and good guy from bad guy. Same goes for role models.
Overall, this was an admirably done movie. For any history loving kids, hopefully there still are, and for those who savor the realism, this is your match. I never really comprehended, before seeing this movie, that people in Germany did try to assassinate Hitler and bring an end to his ruthless Reich. Which also brings to mind this is a good history lesson. I can also say that this might give teens and young viewers and different and clearer view of injustice, violence, and doing what is right. Merry Good Discussions to you!