This study aimed to develop an instructional model for high school classrooms by applying the OECD’s AI Literacy (AILit) Framework to Korean language arts instruction and analyzing its implementation in argumentative writing lessons. To achieve this goal, an instructional model was systematically designed using the ADDIE model and applied in writing classes. The findings indicate that integrating the four domains of the AILit Framework into writing instruction produced substantial changes in learners. Rather than accepting AI as a mere information-delivery tool, learners approached it as an object of critical inquiry and engaged in sourcing and corroboration. Furthermore, by collaboratively producing texts with AI and engaging in self and peer assessment activities, they strengthened their agency throughout the revision process. By reflecting on their experiences with AI, learners internalized proactive and responsible attitudes toward AI use and explored their own principles and ethical standards of engagement. These results suggest that AI literacy education can move beyond technical proficiency to cultivate human-centered literacy that integrates human cognition, language, and ethics.