Advice for California teen(15) 9th grade for big three and WGU accelerated with ACE

[djdja]

Got a teen in my family who has excelled in homeschool for three years, based in California. I myself did running start in Washington state and got my AA in when i finished high school. While such programs exist for 11th graders, they do not appear to exists for 9th. Looking to get him enrolled in the big three or WGU preferably. Very open to community college or duel enrollment, as long as he can start at his age. He has started taking classes on sophia.org and has been doing well. He's fifteen and would be entering 9th grade if going to normal school. Could we get him enrolled in a local community college, or one of the big three schools (or WGU which is his first choice)? thanks.