The Prussian education system is the model for education in many modern nations, including the United States. It is, essentially, a model of mandatory education, in which all members of a country must attend school up to a certain level.
The system was developed in the 18th century. The Kingdom of Prussia funded their school system with taxes, rather than charging students, allowing all citizens to attend for free. At the same time, they made attendance of their schools compulsory. It included eight years of mandatory schooling that attempted to fully prepare students for the modern world.
This educational system instructed students on basic educational concepts, such as mathematics, writing, and reading. At the same time, it also taught things like obedience, duty to country, and general ethics. One of the main motivators for the Prussian education system, interestingly enough, was religious. Various factions, most importantly the Pietists, believed that the deepest understanding of God could come only through a personal reading of the Bible, therefore literacy was important for all people, not just the wealthy.
After the first eight years of education, attendance was no longer free, so typically, only the somewhat affluent were able to attend secondary school. Nonetheless, the idea of providing any sort of education to every member of a country, no matter what their means, was a revolutionary one.
In the early-19th century, a great deal of educational philosophy was being developed in the United States. Many of these philosophers became intrigued by the Prussian education system, and the success it was enjoying in both Prussia and Austria. By the mid-19th century, a number of seminal American educators had traveled to Germany to see how the system was actually working, and they returned to the United States as zealous converts, advocating intensely for the United States to adopt the system.
Governor Edward Everett of Massachusetts instituted a mandatory education policy based on the system in 1852. Not long after, New York opened 12 schools providing free compulsive education for students in their local region. The idea of mandatory education spread throughout the United States from there, gathering strength and speed as it went. Its adoption was in large part pushed by Andrew Carnegie and his Carnegie group, which helped advocate for a teacher certification system, and to help fund various schools in need.
Since its adoption, there has been a substantial and vocal opposition to the Prussian education system, particularly in the United States. Many people believe that, in fact, the adoption of mandatory education has weakened competition among schools and limited their ability to innovate. The argument has seen renewed vigor in recent years, with the push for voucher systems as a way to strengthen private schools.