Former main hall of Gakushuin Primary School, Educational heritage site in Ōdake, Japan

The former main hall of Gakushuin Primary School is a school building from 1899 that combines Japanese design principles with modern classrooms of the Meiji era. The structure shows typical features of this transition period, blending traditional and Western architectural elements.

The building was constructed in 1899, when Japan modernized its school system and adopted Western educational standards. This period marked a turning point where traditional and modern teaching methods coexisted.

Built in 1899 as the main hall of Gakushuin Primary School in Yotsuya, Tokyo, the building served the school attended by children of the imperial and peerage families. In 1936 it was granted to the Shimōsa Imperial Stock Farm for the crown prince's schooling, and in 1938 it reopened as the assembly hall of Tōyama Higher Elementary School. After 1975 it stood in Bōsō-no-Mura, where it was used for the 1960s–70s Sanrizuka protest rallies and later as a music-video set.

The building is located within the Chiba Prefectural Open-air Museum Boso-no-Mura and can be reached by bus. Visitors should wear comfortable shoes, as the museum grounds are spacious and explored on foot.

The hall was built in 1899 for Gakushuin Primary School in Yotsuya, Tokyo, not for the university. In 1936 it was granted to the Shimōsa Imperial Stock Farm for the crown prince's schooling, dismantled in 1973 and rebuilt at Bōsō-no-Mura in 1975. It appears on a 1983 stamp of the modern Western architecture series.