This study aims to describe the planning, implementation, and evaluation of teachers’ management strategies in improving student discipline at SMA Kristen Palangka Raya, in response to recurring problems such as tardiness, uniform violations, low participation in learning, and inappropriate gadget use. Methods: This study used a qualitative case study approach. Data were collected through interviews, observation, and documentation involving the principal, teachers, and students selected through purposive sampling, then analyzed through data reduction, data display, and conclusion drawing/verification. Results: The findings show that (1) strategy planning was carried out collaboratively and systematically through discipline-coaching programs integrated with Christian values, the joint formulation of school rules involving the principal, teachers, the school committee, and students, and initial guidance provided since the school orientation period; (2) strategy implementation was carried out through teachers’ exemplary behavior and consistency in enforcing rules, student supervision strengthened by cooperation with parents, and the provision of educative reward and punishment without physical violence; and (3) strategy evaluation was conducted periodically every semester through monitoring and observation, together with success assessment based on students’ self-awareness, the main obstacles being low self-awareness among some students and limited parental support.