Writing is an important part of learning English, but is also one of the hardest skills for second-language learners. The Kurikulum Merdeka highlights different types of writing, with discussion texts being key to helping students think critically. Early observation showed that many students had trouble coming up with ideas and also struggled with grammar and writing rules. This study aims to describe how well 12th grade students at SMAN 1 Banjarmasin write discussion texts. The research used a descriptive quantitative method to measure students’ writing skills. The participants were two classes, XII-F and XII-I, selected through cluster random sampling. Students were asked to write discussion text, which was scored using Jacob’s rubric based on five aspects: content, organization, vocabulary, grammar, and mechanics. The scores were then categorized using Gay’s classification, with calculations following Sudjiono’s statistical formula. The results showed that students’ overall ability to write discussion texts was in the “fair” category, with an average score of 67.87. Most students did well in content and organization but had problems with vocabulary, grammar and mechanics. None of the students reached an “excellent” level in any area. The study suggests that more attention should be given to vocabulary, grammar and writing mechanics to improve students’ discussion text writing