Excellant Advice from Greg above. My sister and bro-in-law just came back from the Pro-Am at Pebble Beach this weekend. Weather was insanely perfect. Bill Murray signed her pregnant belly. LOL.
Anywho, I'm not sure if you can still drive down Lombard street. I heard recently they stopped allowing the drive. But it's still worth checking out!
Heads up about Alcatraz, when I went there many years ago (and from what I still hear), you have to get your tickets WEEKS in advance. I'd double check that one. Its a must see, but make sure you're prepared with tickets. Walking up to the ticket booth may be a shock when you can only purchase a ticket for a tour in 3 weeks.
We spend quite a few day trips over in Monterey/Carmel with our two kids, but they're much younger than yours. If you really wanna nice drive, head all the way down 1 and hit up Big Sur. There's some gorgeous scenery there and some hiking to some pretty cool spots.
Monterey Bay Aquarium is pretty darn good too. Just try to hit it on a weekday. It gets pretty crowded on weekends.
PS.. When you going? The GF and I were debating heading over to the Monterey/Carmel area for the weekend of my 35th bday on March 22.