In spite of increasing international concern and the long-term effects of bullying on children's development, bullying in early childhood has been overlooked and underestimated, with both children and adults having difficulties in recognizing and understanding it. This study explores how young children respond to bully-themed stories, what and how they expressed in writing letters to characters from the stories, and how their attitudes towards and understanding of bullying have changed through a series of reading, discussing and writing about bullying. Drawing from social-constructivist theory, this study was conducted in a classroom of 20 5-year-old children in a metropolitan city in Korea using a qualitative study approach. The children were involved in a large group reading about bullying and follow-up letter-writing activities led by their teacher. The findings show that the approach used in this study helped children clearly understand and recognize bullying. Specifically, the letter-writing activities after reading and discussing bully-themed stories enhanced their understanding of bullying and helped them empathize with the characters. The children also showed various ways of solving problems/issues and practised getting along with other children. Approaches to more meaningful and effective planning and implementing activities for bullying education in the early childhood classroom are discussed.