Hoshū jugyō kō (補習授業校), or hoshūkō (補習校) are supplementary Japanese schools located in foreign countries. Hoshū jugyō kō take Japanese children who attend local day schools and operate on weekends, after school, and other times not during the hours of operation of the day schools.
The Ministry of Education of Japan (MEXT), as of 1985, encouraged the opening of hoshū jugyō kō in developed countries while it encouraged the development of Japanese day schools, or nihonjin gakkō, in developing countries. In 1971 there were 22 supplementary Japanese schools worldwide. In May 1986 there were 112 supplementary schools worldwide having a total of 1,144 teachers, most of them Japanese residents, and 15,086 students. The number of supplementary schools increased to 120 by 1987. As of April 15, 2010, there are 201 Japanese supplementary schools in 56 countries.
These schools, which usually hold classes on weekends, are primarily designed to serve temporary residents residing in foreign countries so, upon returning to their home country, they can easily re-adapt to the Japanese educational system. As a consequence, students at these schools, whether they are Japanese nationals and/or permanent residents of the host country, are generally taught in the age-appropriate Japanese curriculum specified by MEXT. Article 26 of the Japanese Constitution guarantees compulsory education for Japanese children in grades one through nine, so many weekend schools serving those grades opened. Some weekend schools also serve high school and preschool/kindergarten. Several Japanese weekend schools operate in facilities rented from other educational institutions.