Cotillon Garden RV Park in Felton (near Santa Cruz): (no website)
Casini Ranch in Duncan mills (on the russian river): http://www.casiniranch.com/
Marble Quarry in Columbia http://www.marblequarry.com/
Lake Solano Park in Winters: http://www.co.solano.ca.us/depts/rm/countypark/lakesolano.asp
Olema RV Resort in Olema: http://www.olemaranch.com/
Vierra's Resort in Iselton: http://vieiras95641.tripod.com/
If you are looking towards the Sierra, you will probably have to camp at 3000' elev or higher to escape the summer daytime heat. That will limit choices for full hook-up parks. If you don't mind drycamping, there are a lot of Federal CGs in the Sierra, above 3000' elev, some with group camps you could reserve.
'07 Chevy 2500HD Silverado "Classic" CC D/A 4x4
'07 Komfort Trailblazer T252FS fifth wheel
Reese Signature 18K Slider and other stuff.....some useful.....some not
When I was station at Beale AFB my family and I went camping at Donner State Park during the summer time. I rate that place a 9 out of 10, during the day it was the perfect temp. and at night it got cold.
Thank you for all of your suggestions so far. We are planning to go in early August. The kids also enjoy being able to ride their bikes, and there are several hiking enthusiasts. To those who suggested Camp Edison, would it be hard to get reservations?