I still remember my trip to Science museum quite a while ago as the experiments on display were no less than pure magic. Things like pendulum balls, tube water oscillation, bubble traps were just amazing.
One fine museum that you missed is the Ann Arbor Hands-On Museum (www.aahom.org). Both kids and adults love it. I'm partial to it because I am the station manager for the museum's amateur radio station, WA2HOM.
@Susan, this is absolutely a gem! I lived in the Bay Area for almost 10 years, and I never knew about this place! Besides the story about the city of Oakland used keep their own time is such an interesting piece of history! Next time when I come back to the area, I am definitely going there!