My list of less selective but very credible CA schools for CS includes UCSC, UCR, UCM, SDSU, SJSU, Cal Poly Pomona, CSULB, Fullerton, Chico, Northridge and LMU. Some of those are more competitive than others and I am probably leaving a few off but, you get the idea.
Truth be told, most of the CSUs have respectable CS programs. Even Sac, Sonoma, East Bay, SF, and Fresno see recruiters from top tech companies. Coding and system design are tangible skills in short supply. If you can deliver results, your employer really doesn’t care where you went to school. In fact some of the non-college ‘coding bootcamps’ are viable options for the passionate student who wants to get into the workforce ASAP.
I would add that many (perhaps most) students who enroll as CS majors as freshman change focus and graduate with a degree in some other field of study. It is an intense program at most schools and it ain’t for everyone. Pick a school where your son will be happy for 4 years - no matter what he studies.