If throwing money at a problem fixed it, then every child in Australia should be a genius by now.

But halfway through a 10-year, $320 billion funding injection known as Gonski 2.0, the academic performance of Australia’s 15-year-olds in maths, science and reading continues to slide. The decline is most exaggerated among the poorest kids, who the Gonski reforms were designed to help, but even in the upper tiers of privilege and advantage there is a real slip in performance.