We got a season pass to the exploratorium as a gift this year and took full advantage on this New Year Day. As an uber-geek, I enjoy the hands on exhibits and do my best to explain things to the kids without going too far over their heads. I usually fail miserably, but they seem to like playing with all the various items despite my pontificating. Before I lose you as well, here are some photos of the day.
A corner reflector display Ashley liked:
This penrose triangle is a real thing… but is not possible as it appears. See the link for how they did it: