This article explores the relationship between the freedom granted to teachers to shape curricula and the function of national standards. In recent years, many countries have begun to introduce standards-based reforms in education, such as standardized curriculums and high-stakes tests. As cultural diversity within schools increases, the tension resulting from catering to this diversity while maintaining standards is also rising. This article offers a comparative analysis of the educational theories and practices in the U.S. and Japan. In the U.S., debate and conflict between supporters of national standards and those of multicultural education have surfaced. In Japan, the government determines broad standards for all schools in order to ensure a fixed standard of education throughout the country. Thus, although the U.S. has a higher degree of cultural diversity than Japan, similar controversial issues will also face the Japanese educational system as school populations change rapidly due to the enrolment of children with diverse foreign heritages. Therefore, this article advocates the need for balance between the scope of regulation by the national government and the development of a citizenship education curriculum that uses teachers' own initiative in the modern age, and has practical implications for educational policymakers.