The courses are approved by UCOP (University of California, Office of the President). It’s not approval of the course provider; it is approval of the individual courses. themselves. A California high school, no matter how prestigious or well-respected, can’t simply add a new course to their roster and have it count – it has to go through the approval process to get it added to the approved list.
When students fill out an application online for the UC, they can select their high school and then fields for reporting coursework are automatically filled by the list of approved courses at their school.
Information here: http://www.ucop.edu/agguide/updating-your-course-list/
If the student has graduated from a California high school, they need to complete the A-G subject requirements to qualify for the preferred pathways for admission-- the ones that come with the guarantee. And that is the path that most high school students will follow, unless there is some reason they were unable to complete the requisite coursework.
Admission by test scores alone is a different, less-favored option. Yes, a high schooler short on the A-G requirements, but with a 2250 SAT probably would be on equal footing with a home schooler… but either way, those students are at the end of the line as compared to the students who have guaranteed admit status with the requisite coursework & GPA, even with significantly lower test scores.
About 15 years ago, before the opening of the Merced campus, there was a year when the campuses were full up, and the UC system could not honor its guarantee. Some students who should have been guaranteed admission were shifted to the community college path. The Merced campus was essentially created to meet the demands of the increasing UC population. It’s probably unlikely to happen again, but it still impacts chances of admission.
I wrote that it was a disadvantage in relation to predictablity.
I don’t rely on “feelngs”. I rely on published information on the UCOP web site:
http://admission.universityofcalifornia.edu/freshman/california-residents/index.html