California - best things to see with young children?

[AAAvegetable]

We are going to a wedding in California next summer. After the wedding we will have 4 weeks to travel around the state. It will be August. Our DDs will be nearly six and three and a half.

The wedding will be near Santa Cruz but we can travel a bit. We will also visit friends in the Bay Area.

What are the best things to do? I am not thinking of Disney/Universal Studios etc, I want outdoor activities. My ideal would be a trip to Yosemite but its already too late to get a cabin actually in the park and I don't want some huge hotel on a road an hour away. I also wander if the girls are too young for a big park like Yosemite. It is not like we could hike far. Are there any smaller parks that people would recommend? Any particularly nice coastal areas?

All tips gratefully received.

Bump.

There are TONS of great things to do in the Bay Area Ca (just saw that you'll be there for a month, and touring around the state). Off the top of my head:
-Monterey Bay Aquarium (and the rest of Monterey)
-Muir Beach and Woods (though IIRC there are some good woods and beaches closer to Santa Cruiz)
-they're probably too small for Alcatraz, but I liked it as a 9 year old
-I've heard that Angel Island is good
-A must-visit for the little ones is Oakland Fairyland
-SoCal is where you want to go to the beach- the water comes down from along Alaska in NorCal and is really cold!

-Lake Tahoe was before all the pollution and decreased water levels is gorgeous- deep, aquamarine-blue, surrounded by pine trees...
-try to visit some of the gold country stuff/ghost towns (ex mining) and the like (or Sutter's fort) if you can, it's really interesting

erm, yeah, can you tell I grew up in CA

San Diego for Sea World and the awesome zoo. Calico ghost town near Barstow perhaps?
Lake Tahoe is pretty, but parts of South Lake Tahoe City are really seedy.

re Yosemite - have a look at Yosemite View Lodge it is only 20mins from the entrance to the National Park. Nothing to look at but it has the massive advantage of having a pool(s). Massively cheaper than inside the park too. We "did" Yosemite in 3 days this summer with older kids and I would suggest that is enough. San Fran weather disapponting in July!

Yes, I agree about the weather in San Francisco. We were there at the beginning of August and managed a massive 19 degrees on the warmest day. A bit of a shcok after having driven through Death Valley the week before.