>US schools have among the highest per-student funding in the world.
We actually looked at this in comparative econ, and I believe that the statistic is misleading, at least if it leads us to conclude that teacher quality should be higher in the US. You must correct for the alternative jobs available to the type of person who will become a teacher. In the US, since per capita income is higher, people who are deciding whether to become teachers or not will have to be offered higher salaries in order to do it because the alternative is more attractive, so the fact that per-student funding is higher in the US is actually the least we should expect, not some surprising statistic.
There are a few questions worth asking about this, though: Do those numbers include benefits? American teachers may get more of those than overseas teachers. And how skewed is that data by the very rich in America?
The US is "below trend" for per-student spending vs GDP, fit linearly. Not by a huge amount, but it might be wrong to go on about how generously American schools are funded.
That does depend on how the money is spent, though. Wages might be higher in places that are more developed, but it's not clear that materials should be more expensive there.
Some of US teachers' retirement and healthcare benefits would be unnecessary in countries with proper social systems, so I don't think they should be counted in comparisons.
In most US states, schools are nominally independent bodies of government, they carry all of the costs of facilities, pensions, etc. They also need to comply with all sorts of cost enhancing building and labor standards.
So in my city, the school collects $28k/pupil. That includes something like $150M in debt for buildings, salaries, 20% of salaries for pension obligations, 15-20% for employee healthcare, key expenses for the various charter schools, etc.
They also need to deal with compliance issues. Because some redneck place in Mississippi would give poor kids a slice of Bologna and stale bread, there are prescribed calorie and nutrition standards that get audited. So you can't prepare fresh foods.
Students also probably don't want it. Fresh foods don't keep as well. I always felt more comfortable eating "crappy" food at school because it's hard to mess up. A couple wilted leaves in a salad doesn't really actually affect the quality, but it does turn you off from eating it. There's no where for me to wash the apple they gave me that was handled who knows how and possibly not washed before I'd be eating it.
The Chipotle debacle provides a bit of evidence that fresh and local isn't necessarily the easiest to quality control.
Why does having prescribed standards prevent fresh foods? It's not that difficult to work out the nutritional value of commercially cooked food, you'll already know portion sizes and what ingredients go into that in order to plan how much you need to feed everyone.
Perhaps that money should be going into school lunches instead of wherever it is going at the moment...