In the period of the Three Kingdoms of Korea (57-688 AD), the governments began to institute education. The education system was heavily influenced by Confucianism and Buddhism.
Goguryeo Period
Goguryeo was established from 37 BC to 668 AD. From its establishment, it was already using a form of writing. It is best demonstrated by the book Yoogi(유기; 留記). The first established institution was Taixue (태학; 太學), also called Daehak. It was established at 372 AD. The institute was mainly used by the Yangban class. It was established with Confucianism as its philosophy of education. Later, Buddhism was added to its curriculum. It thought both the humanities and martial arts. There was also another institute called Gyungdang. It is thought to be established at 372 AD.
Baekje Period
Baekje was established from 18 BC to 660 AD. Evidence of the scholarly method can be seen through the Japanese books of Nihon Shoki and Kojiki. It can also be seen through cultural exchanges with Japan, such as the transference of the books the Analects and the Thousand Character Classic at 258 AD. Further evidence of education is shown in the history book Seugi (서기; 書記)
There are no records of an established institution. However, references to an establishment can be seen through various posts establishing relations with Japan. The Consulate General of the Republic of Korea holds that educational institutions were found earlier than 372 AD.
Silla
Three Kingdoms Period
Silla was established in the Three Kingdoms Period from 57 BC to 668 AD. The government mostly focused on the martial arts because of the invasions from the surrounding kingdoms. The main educational institute is considered to be Hwarang.
Unified Silla Period
Unified Silla was established from 668 AD to 935 AD. Education besides Hwarang began to be established after foreign influence. There were several student exchange programs with China. The major establishment is Gukhak (국학; 國學). The curriculum was directly taken from the system of the Tang Dynasty. It was established at 682 AD. Most of the subjects were humanities.