Toshiro Kanamori teaches a fourth-grade class in Kanazawa, Japan, and treats emotional education as seriously as arithmetic. The camera sits in his classroom for a school year, watching him have students read aloud letters about grief, illness, and family hardship while their classmates listen, cry, and respond. One boy struggles with anger after being teased; a girl processes the death of her infant sister through a letter she reads to the room. Kanamori's method is blunt: he tells children that hiding pain makes them weak, and that a classroom can function like a family if everyone is honest about what they feel. Between these moments there is ordinary school life, arguments over lunch, group singing, kids working through disagreements without a teacher stepping in to referee. The film does not add outside commentary or experts; it simply records a teacher's unusual experiment in building empathy among nine- and ten-year-olds, and lets his students' own words carry the argument for why it works.