I've taken pupils of around eight years old to Norwich Castle many a time, and they were horrified at the cruel things that the guide showed them.
I reckon though that they were already in 'fear mode' as he'd turned off the lights to show what it was like for prisoners in the deepest dungeons. It always stayed dark for just a bit too long...

I often felt a little hand grope for mine and another one holding on to my coat before the lights went on again.

I wasn't feeling too chipper myself to be honest!