The second day we were in CA we bought a pass to the San Jose Children's Museum. We spent 5 days a week there in the afternoons. The museum is large and has a ton of rooms. We had a lot of fun there. Our two favorite rooms were the Bob the Builder traveling exhibit room and the water room. For as many days as we spent there I should have more good pictures, but here are some of my best.
Mark could not have been happier about playing Bob the Builder.

The kids got soaking wet every time we went into the water room. After the first day I bought an extra set of clothes with us. The room had a lot of fountains (that Lilly was sure were for drinking) and a lot of ways to move plastic balls around.
One day, while Lilly was napping in the stroller, Mark spent close to an hour playing with this magnetic board and the movable troughs. Water comes out of the two round nozzles at the top. He made many different configurations for getting the water to the bottom. It was really fun to stand back and watch what he was doing.
This is an actual old stagecoach. The first time we walked by it Mark went right in and started playing house. Lilly liked climbing up and down the stairs.
There was a hole room filled with these large blue building blocks. Mark built lots of things with them, including helping another family build this fort. Lilly loved knocking down whatever I would stand up for her.
The museum has an old fire engine for playing in. The kids didn't spend too much time playing in it, but because they were contained in it I could get some photos of them.
Look at this cute boy! Those blonde curls are so adorable I can hardly stand it.