More thoughts on stuff to do in California:

visiting the California Science center

The Science Center is free to visit. However, the IMAX theatre does charge, and for a large family, $4 each really adds up, especially if you visit often.

We usually get a family membership. It's about $40 a year, and includes some free IMAX tickets, free parking passes, and free tickets for some of the few features of the science center that has a charge. (Like the high-wire bicycle.)

The value of the free tickets more than covers the cost of the family membership.

Additionally, people with family memberships can see IMAX movies free! (On Tuesday, I think... perhaps it has changed, though.)

It's really a good investment, I think.

When you have a lot of kids, you discover that a few family memberships is actually cheaper than going out to the movies once a month, or even just renting a movie and getting pizza! (3 or 4 pizzas really add up...)

Here's a good course on money that has really helped me a lot:
Church of Scientology: Dynamics of Money Course