Paper Title
STUDENT ARGUMENTATION IN SOLVING MATHEMATICS TASK

Abstract
This study describes students’ argumentation skills in completing mathematics assignments in adaptations of PISA and TIMSS questions. The research subjects were selected by considering the initial mathematics ability test results in class VIII of SMPN 13 Banjarmasin. Then, students were grouped into categories of high, medium, and low mathematics abilities. From each category, one student was selected as a research subject by considering their communication skills to make it easier for researchers to find out the details of the student’s process in completing the assignment. The mathematics assignments were two tasks adapted from PISA. and TIMSS related to algebra topics, where each task consisted of 2 parts. Then, the tasks were continued by interviewing each subject. The results of the subject’s work and interviews were then analyzed using the Toulmin model. The results of the study showed (1) subjects with high mathematical ability were able to demonstrate all components of argumentation in all tasks given, (2) subjects with moderate mathematical ability, in the first task, were able to demonstrate all components of argumentation, but in the second task were unable to provide a claim because they were unable to understand the problem so that the data provided was not appropriate, and (3) subjects with low ability, in the first task (a) were able to demonstrate all components of argumentation but in part (b) students were unable to claim because they were unable to make a warrant that could connect the data and claim, in the second task students were unable to understand the information that was the basis for making a claim. Keywords - Mathematic Task, Argumentation, PISA, TIMSS.