This study investigated how keeping a journal related to issues and concepts in science influences sixth grade students’ affective characteristics, including cognition, interest, and attitude towards science. The development of these characteristics is related to students’ attitudes and interests in learning. Previous studies have primarily focused on the affective characteristics of gifted students, while only a few have focused on elementary students in public schools. We asked 34 grade six students in Korean public schools to keep a journal related to science and technology three times a week for 12 weeks (September–November 2018). The results show students’ perspectives on writing science journals from data, including questionnaires, interviews, and surveys. The results also suggest that keeping a science journal develops students’ affective characteristics related to science. Our findings will contribute to the development of better pedagogies for sustainability and resources for teaching science among elementary students.