@sozobe,
I saw photos of Dachau when I was ten, some government pamphlet, something like 1951 that I saw it. I suppose I've never been the same, and that was in my own house. I don't remember the circumstances, whatever my parents might have said, or even how I saw it. I was a nosy kid. Just remember the pamphlet, that I still have.
All in all, I'm glad I knew that - sort of a grounding.
On the other hand, the thing in your daughter's class seems what I would call iffybody - no parental permission.
That there was not counsel before or after, unforgiveable.