> Are you aware that the U.S. spends among the most on primary education
Yes, and I'm also aware that in the US we expect the public school system to be a primary treatment center for the disadvantages and traumas associated with poverty and unequal opportunity.
It's more expensive (and harder) to educate hungry, ignored, and traumatized children than it is to educate children who are well take care of. They need more support staff, more psychologists, more free lunch programs, after-school care that their parents can never afford. And it's hard to attract good teachers to teach academics in those circumstances.
The major problems with primary education in the US are largely faced disadvantaged communities, not prosperous ones. If we decide to remove educational funding from disadvantaged communities, we have to be prepared to either put it into those communities in other ways, otherwise we'll face even greater problems in schools.
None of that is to say that there doesn't need to be more accountability in school systems - there is a lot that needs to be done to re-examine how education is delivered. But just looking at the situation by comparing $ spent on primary education between countries is oversimplifying things.