If we are judging by one completely objective measure (high school graduation rates) California is currently the lowest-ranked state in the country: https://worldpopulationreview.com/state-rankings/high-school...
I wonder if something else is going on for California and Texas to rank behind Mississippi, Alabama, and Louisiana? I'd bet that the issue with the standard of measure, not the actual quality of education.
I should say I think its schools are fine, rather than great.