As I’ve pointed out elsewhere, based on income and education levels of parents, Poway school district actually underachieves, although Poway High itself is quite good, it’s the other High Schools in the district that are mediocre. Carlsbad High also underperforms based on parental education and income.

If you could estimate total investment per pupil including parental contribution (tutors, music lessons, test prep courses), you’d probably see that Poway, Carlsbad et al actually spend a lot more per pupil to get the results they do. The burden just falls heavier on the parents, most of whom can afford to do so.