In this article, learning and other different activities in school education were explained from the perspective of self theories. The self-other relationship is the basis of self theories. It was explained from different angles: the structures of daily conversation, the etymology of the self, and the mechanism of early childhood in human development. For school education, self theories suggested that learning requires the self-other relationship: practically learning through dialogue. Last, constructing personal lives was also explained through the multiple self and the dialogical self. As the extent of modernity in society progressed drastically, people’s individualization and individuation were also developing. These social changes created career education in school curricula, which changed students’ learning: it was not only for acquiring knowledge and skills but also for forming their selves for the future.

This study developed a scale to enable high school students to self-assess their digital competencies, which are essential in the information society. The scale was constructed by referring to the European Commission's DigComp framework and DigCompSAT, and by focusing on the missing concepts and elements in Japan's Joho-Katsuyo-Noryoku (information literacy). A study of 732 high school students was conducted using the scale. The confirmatory factor analysis demonstrated a good fit for a bifactor model consisting of group factors corresponding to the five areas of DigComp, which confirmed the construct validity. The model was also maintained in the 20-item scale, which was condensed from the initial 82 items. The model showed an acceptable level of internal consistency by omega, and group discrimination validity was confirmed by using IC3 as an external criterion. Therefore, we concluded that the high school student version of the digital competency self-assessment scale is generally valid.