I'll make a secondary school/grammar school which will focus exclusively on learning maths all the way to algebraic geometry and philosophy all the way to German Idealism and Whitehead, which is because those two touch on abilities and knowledge that are transitive and can be improved. Individuals which will successfully undertake such a school will then take an extended matrix reasoning test with far too many items to be completed composed exclusively of difficult items at 16, that is to say if they manage to pass that school, and then the very best will be accepted into "The Demiurges", where their Raven's results will be concealed, but the system will be deliberately designed to attribute higher status to younger individuals, due to fluid intelligence decline. It will plausibly be akin to a PhD program in nature, and all of their student loans will be payed for, they'll be housed for free, and they'll receive free food and other base necessities.
This is because the drastic majority of things learned in school beyond elementary school, which teaches counting, reading, and writing in the very simplest of terms, is absolutely useless drivel of the nature of jerking about semantically vacuous content, such as how you say frog in a part of the world that doesn't want to learn English or when a certain queen shat her pants due to dying after being beheaded. Beyond elementary school, schools are not schools, as much as they're indoctrinating mental wards of crazed seniors that serve to daycare the physically inept for which it is illegal to work by vomiting on them the equivalence of a retiree's hobby.