Purpose: To prevent and respond to youth sexual problems that are becoming more serious with digital development, this study sought to develop a sex education program that applies gamification as an effective method for youth who are digital natives. Research design, data and methodology: To develop a sex education program for teenagers, elements of gamification were considered based on Dick and Kerry's teaching system design model. The learning content reflected UNESCO's 'Comprehensive Sex Education Guidelines'. In addition, it was designed to enable students to learn about ethics and morals from a social and emotional aspect. Results: A four-session distance learning sex education program was developed for first-year high school students. To learn about gender sensitivity, sexual relationships, sexuality, and healthy sexual behavior, we developed a story that reflects the mission and quest for sex education. It included leaderboards, time limits, and levels, and also utilized mechanics such as points and items. Edutech tools include video content, Google Sheets, Zoom, Padlet, and Mentimeter. Conclusions: This study aims to improve learning effectiveness, satisfaction, and immersion by developing a sex education program for youth using gamification that promotes active learner participation and motivation.