There are two research questions addressed in this paper. Generally, Social Studies is the subject of “citizenship development through social recognition.” The first question is concerned with the way of thinking about the relationship between social recognition and citizenship formation. It is a question of the “big story”, that is the normative and fundamental question of “What is Social Studies.” Social Studies that prioritizes the former (social recognition) are called “narrow Social Studies”, and Social Studies that prioritizes the latter (citizenship formation) are called “broader Social Studies.” In this paper, from the viewpoint of citizenship education and the fostering of a sustainable society in the current Japanese course of study, I insist on the importance of “broader Social Studies” from the standpoint that “Social Studies as Citizenship Formation” is necessary. The second question is concerned with the “small story”, that is a practical question for Social Studies. It is a question about how to make lessons in daily Social Studies classes as a teacher or a practitioner. As a high school teacher, I designed and taught many lessons of Social Studies. As a practitioner, through the process of trial and error, I have been making and implementing lessons of Social Studies from the perspective of fostering global citizenship with the aim of international and global education, and I came to be engaged with “broader Social Studies.” Both as a researcher and a practitioner, “Social Studies as Citizenship Formation” is the center of my social studies design.