<![CDATA[Critical and effective argumentation is one of the essential competencies students to should develop in learning argumentative texts. However, many students still experience difficulties in expressing logical opinions, providing relevant facts and evidence, and delivering critical and appropriate rebuttals. This study aims to improve the argumentation skills of eleventh-grade senior high school students in learning argumentative texts through the implementation of the Active Debate Method. This study employs Classroom Action Research (CAR), conducted in two cycles consisting of the stages of planning, action, observation, and reflection. The research subjects were the students of Class XI-A1 at SMAN 9 Surabaya. The data were collected through argumentation skill tests, observation sheets of teachers' and students' activities, documentation, and field notes. The data were analyzed using descriptive quantitative and qualitative techniques by comparing the results obtained in each cycle. The findings indicate that the implementation of the Active Debate Method improved students' argumentation skills, as reflected in their increased ability to express logical opinions, use relevant facts and evidence to support their arguments, provide appropriate rebuttals, and participate more actively during the learning process. Therefore, the Active Debate Method is considered an effective instructional strategy for improving the argumentation skills of eleventh-grade senior high school students in learning argumentative texts.]]>
