During World War II, many Japanese students were enlisted to actively help in the war effort, effectively turning schools into factories. Bombings destroyed many schools. After the Japan's defeat of the war, this left a lot for the occupation forces (SCAP) to help rebuild.
The occupation team addressed the educational system. The Japanese methods were nearly opposite to that of the United States: control of schools was highly centralized, rote memorization of book knowledge without much interaction described the standard student-teacher relationship and the study texts were described as boring. The ratio of school years was made to resemble that of the United States' which was 6 years Primary education (elementary schools) : 3 years Lower Secondary education (junior high schools) : 3 years Upper Secondary education (senior high schools) : 4 years Higher Education (Universities or colleges). Over the period of occupation, these and many other trends were changed. A less centralized hierarchy of school administrators was introduced; totally unprecedented, parents were allowed to vote for school boards. A new textbook industry was created.
However, after the end of occupation, much of Japan's educational system reverted to the older system.
Much of the reform was focused on conditioning students to more readily accept democratic, liberal and egalitarian ideals, directly competing with the prevailing hierarchical structures deeply ingrained in every level of Japanese society, from family life to government institutions. Classes became co-educational single track system composed of 9 compulsory years, moving away from the former 6-year, single-sex, multi-track system. The use of kanji script was overhauled and greatly simplified, eliminating all but 1,850 more commonly used characters, referred to as the tōyō kanjihyō.
Initially, before the Japanese Ministry of Education (MEXT) and Allied command's Civil Information and Education Section (CI&E) produced new textbooks to replace them, narratives in existing Japanese textbooks found to extol feudalistic, nationalistic, militaristic, authoritarian, State Shinto-religious, or anti-American views were censored during class by students through a process of Suminuri-Kyōkasho, or "blackening-over textbooks" with ink, under orders of the Supreme Commander for the Allied Powers (SCAP).