The government, politicians and bureaucrats, decide what government schools teach. The schools are little more than government indoctrination centers. This was because the States were acting together but considered individual political units. Schools no longer teach any of this because these ideas tend to diminish the government's power. The government craves more power so in government schools it indoctrinates children to think in terms of government granted privileges and government supplied services.
Government schools produce people who look to government to fill their needs.
They have no place in a free society. Government schools did not exist in this country until about one hundred years ago. Since the first government school opened, government schools grew in power and size until they all but eliminated private sector schooling. The government drove people from private schools by using the power to tax. As the government striped ever larger amounts of money from individuals, fewer people could afford private or home schools.