I am not sure if there are State Standards for preschool in California since it is not required.
However, here is some information I found on the California Department of Education website:
"A quality preschool curriculum that supports a three-to-five-year-old's optimal learning has certain indicators of effectiveness, including (1) children are active and engaged; (2) goals are clear and shared by all; (3) curriculum is evidence-based; (4) valued content is learned through investigation and focused, intentional teaching; (5) curriculum builds on prior learning and experiences; (6) curriculum is comprehensive; (7) professional standards validate the curriculum's subject matter content; and (8) the curriculum is likely to benefit children" http://www.cde.ca.gov/eo/in/se/yr05preschoolwp.asp
The website provides more information about developing high quality pre-K content standards. I hope you find this information helpful.