Going to Yosemite, etc

[Gambit]

My grandfather's 90th birthday is in less than a month. So a bunch of us kids and grandkids are going to go visit him in California. I bought and fixed up an old popup camper and we're going to make a big family vacation out of it. We'll spend some time in the area north of Fresno where they live, a day in San Francisco, a couple of days at Oakhurst & Coarsegold (south entrance to Yosemite) and a couple of days at Morro Bay.

So, I'm looking for suggestions from those of you that have been in that area. What shouldn't I miss, photographic and otherwise? I had definitely planned to visit the grove of giant redwoods, and get into Yosemite Valley. The falls will likely be a trickle, if that, in August. What else to see?

(I also want to figure out a way to take a wide-angle lens on the trip; my widest right now is the 18-55 kit from my 20D.)