> The US spends more per pupil than every other OECD country except for Luxembourg, and exceeds the average by over 50%.

Not accurate in the context you're saying it.

You're probably conflating US K-12 spending (low) with post-secondary spending (high)?

https://nces.ed.gov/programs/coe/indicator/cmd/education-exp...

https://educationdata.org/public-education-spending-statisti...

> US K-12 spending (low)

Your source there still puts US K-12 spending in the top-5 worldwide.

The allocation of said spending clearly isn't optimal, but there is plenty of money at a high-level

Educational spending in the US is individual to the state, and even more locally within school districts within states, so it makes no sense to look at it from a national average

Bizarre; why are their outcomes relatively poor?

Wild guess: maybe most of the spending goes to the school football team?

It doesn’t work that way