<![CDATA[This study aims to determine the effect of the Problem Based Learning (PBL) model assisted by Augmented Reality (AR) application media on the mathematical critical thinking skills of fourth-grade elementary school students in plane geometry material. This study used a quantitative approach with a quasi-experimental method and a non-equivalent control group design. The research sample consisted of 17 students in the experimental class and 17 students in the control class. Efforts to improve students’ mathematical critical thinking skills can be carried out through the implementation of the Problem Based Learning (PBL) model assisted by Augmented Reality media, which encourages students’ active involvement in the learning process. This study aimed to: (1) determine the improvement of students’ mathematical critical thinking skills who received the Problem Based Learning (PBL) model assisted by Augmented Reality compared to Discovery Learning assisted by PowerPoint, and (2) determine the effect of implementing the Problem Based Learning model assisted by Augmented Reality on improving students’ critical thinking skills. The method used was a quasi-experimental design with a non-equivalent control group design. The subjects of this study were fourth-grade students of SDN Pantai Mekar. Data collection techniques used tests and documentation. The results showed that: (1) the improvement of students’ mathematical critical thinking skills through the Problem Based Learning model assisted by Augmented Reality was better (81%) than the Discovery Learning model assisted by PowerPoint (72%), and (2) the effect of the Problem Based Learning model assisted by Augmented Reality was 37.3%. Thus, the model was effective in improving elementary school students’ mathematical critical thinking skills.. ]]>
