I am 26, dh is 24 and we were both hs our whole lives. California was perfectly fine when I was growing up. Most of our friends were part of a "private school" homeschool group and filed affidavits with the State, but my Mom rebelled against that and we never filed for one. I did standardized testing ONCE in 5th grade, but we got by just fine without reporting our business to anyone. We also did not live in fear and went out in public during school hours. Several times we were questioned by strangers, to which we would reply, "life is school!" and they would laugh. We never had any serious issues, though.
My dh, brothers and I finished highschool at age 16 by taking the California High School Proficiency Exam (equal to the GED but you can take it in the 2nd semester of "10th grade"). My friend flunked it, but went on to community college and became a CNA by age 17, and is now going on to be an RN (she was just nervous as it was her first big test outside of her kitchen classroom).
We had a great network of hs friends, and being a big tourist area we actually didn't get that many funny looks being out during the day as there are tourist kids everywhere. We have access to so many things living in the Palm Springs, CA area....the mountains a 1 hr drive, the beach a 1.5 hr drive, Joshua Tree National Monument 30 mins away, museums and places galore for field trips in the San Bernardino, OC and LA areas just a days drive away.
I wouldn't change a thing about my hs experience growing up in California.