Science Center Spectrum, Berlin

Recently I've visited the the Deutsches Technikmuseum and the Science Center Spectrum in Berlin. I can really recommend both for you and your family. My kids enjoyed the science center with lots of hand-on experiments explaining physics. The section about the optics was extremely cool and there was a demonstration explaining how the optical fibers work. I tried to take a photo but it was pitch dark:

At the next station you can manipulate prisms and lenses:

The Deutsches Technikmusem has a very nice exhibition about the history of the photography. My children were too tired so I left them with my wife and I just rushed through the exhibition. his small showcase was devoted to underwater photography:

Some cool old classic lenses were also exhibited:

The museum and the science centre is next to each other and you have to buy only one ticket for both.
Highly recommended if you visit Berlin.