Historically and culturally the efterskole is related to the Danish free school movement, and the efterskole is often regarded as a junior form of the Danish Folkehøjskole (Folk High School).
The important role of the Danish Folkehøjskole in the development of democracy and the transformation of Danish society in the 19th century (co-operative movements, changes in political, educational, religious, and judicial systems) is well documented. And the Folkehøjskoles, of which the first was founded at Rødding 1844, are recognised as Denmark's most original contribution to international education.
N.F.S. Grundtvig (1783-1872) - bard, poet, educational thinker, politician and clergyman - was the founder and visionary genius of the Folkehøjskole movement, but it was most notably Kristen Kold (1816-1870) who transformed Grundtvig's visionary ideas into educational practice.
While Grundtvig intended the Folkehøjskoles to be for adults, Kold wanted to reach the young people when they entered puberty. Thus Kold's first school, founded at Ryslinge in 1851, was for young farmhands, and this school is recognised as the first efterskole.
For Grundtvig, schools were to provide enlightenment for life rather than formal or vocational training. Therefore, they should be free from any kind of examinations. The teaching style was based on "free, open poetic-historical talks", without fixed syllabi, but with emphasis on human enlightenment. The learning environment would make a strong cultural impact, by means of "the living word", creating in young people a receptive attitude, and bringing the students into a concrete relationship with the practical aspects of life.
The initial target group (in the agricultural society of that time) was the young rural population. At the efterskole or at the Folkehøjskole these young people were encouraged to supplement their basic elementary school education (7 years) with free studies, thereby creating a counterculture whose members would be in a position to exercise the instruments of democracy which were introduced with the first free Constitution in 1849. In other words: the idea was to develop the peasantry from a group of subjects to a group of participating citizens.
A famous anecdote concerns how Kold met a young farmhand out in the fields and tried to persuade him to come to his efterskole. When asked what good that would do a future farmer, Kold asked him if he had a pocket watch. Yes, he had. "That watch," said Kold, "can go for a time, and then it has to be wound up again, but at my school you will be wound up so that you will never stop!"
For at more detailed description, please see the flyer "The Free Danish School Tradition" (pdf)
The educational ideas of Grundtvig
"People learn by talking with each other". Watch the 10 minutes discussion of the educational ideas of N.F.S. Grundtvig with Clay Warren, a professor of communication at George Washington University and author of The School for Life: N.F.S. Grundtvig on the Education for the People.
Video om Grundtvig: