While researchers agree that note passing is predominantly an activity engaged in by girls, there has been relatively little consideration of why this is the case. In this article, I argue that gendered expectations about the appropriate characters of boys and girls in Vietnam are incorporated into the disciplinary framework of schools, and that note passing provides the means for girls to adjust to the gendered disciplinary techniques to which they are subjected. The article is based on extended ethnographic fieldwork conducted within two ninth-grade classes at two lower secondary schools in the northern Vietnamese port city of Haiphong.