> Like how would AP courses benefit a rural schoolkid other than maybe getting access to work in a city? Could we think there is any education for him to be a good farmer?

I think this perhaps misunderstands the typical life paths of rural students.

20% of the US population lives in rural counties, but only 2% of the population works in agriculture. And even that over-estimates the number of school children who will grow up to be farmers because a huge amount of the unskilled farm labor in the US is done by first generation migrants.

So the average rural schoolkid in the USA isn't going to work on a farm (and the ones that do will often be skilled workers or owners and will therefore go off and get agricultural degrees.)

The government runs a lot of jobs programs for rural areas. Things like state/federal prisons and military bases are intentionally placed in rural areas to provide employment opportunities. And of course national forests/parks tend to be in rural areas and provide a small but steady stream of jobs. We also explicitly subsidize hospitals and schools in those areas; the local tax/consumer base probably couldn't support those services on their own. So the government sector is the lifeblood of many small towns these days, at least as far as employment goes.