San Francisco: Exploratorium
Our first exploit in SF was to take Saskia to a hands-on science museum called Exploratorium. She loves a similar place in Copenhagen called Experimentarium which is clearly modelled on this place. It's housed in the Palace of Fine Arts, one of the few remaining buildings from an exposition in 1915 to celebrate the completion of the Panama canal. According to the brochure there are more than 600 experiments there. Even though we were there for more than 4 hours we can't have looked at more than a fraction of them. I recognised some of the exhibits from Experimentarium and some from the Natural History Museum in Stockholm, so clearly there is some kind of "factory" for interactive science exhibits somewhere!
A particularly spectacular exhibit was actually inside a huge hollow pillar in the colonnade outside, where you could make various frequencies by banging gongs, and by standing at different heights you could examine how they made standing waves in the column. I asked the staff there if it didn't drive them crazy but they said they only had to work there for half an hour at a time! In the grounds there was a lake where Saskia spotted some turtles swimming.
We decided to leave the car at the hotel and take public transport, since the latter is so well developed in SF, in stark contrast to so many other American cities. We'll see in due course whether this was a wise decision...