Till K.
Yelp
This is a pretty comprehensive exhibition of all things GDR. I haven't seen it so detailed and yet so interesting in a long time. And it's also free, which is sort of amazing too.
But what really, really puzzles me that it's all in German and not translated into other languages such as English, French, maybe Spanish? I'm not sure why those people forgot that. It would be perfect otherwise.
I'm not sure if you can get a tour guide from them who explains and translates all the info, but something like that would be necessary if you take people to this exhibition who don't speak any German.