I get a little suspicious whenever education is discussed purely in terms of IQ deltas. Most of the leverage seems to come from giving people repeated chances to practice the handful of “intelligent” behaviors that IQ tests reward: working memory exercises, analogies, pattern completion. That’s useful, but it’s not the same thing as raising a person’s underlying capacity to navigate messy real-world problems.

What I’d love to see in these meta-analyses is a breakdown by instruction style. Content crammed through lectures probably does little beyond test familiarity, while project-based or apprenticeship-style programs often force you to build executive function—prioritizing, negotiating, moving from fuzzy requirements to concrete output. My hunch is that the latter matters more for what we informally call intelligence, but we rarely measure it because it’s harder than handing out Raven’s matrices.