<![CDATA[The issue of low mathematics achievement among fifth-grade students at SD Negeri 1 Banjar Anyar, particularly in the topic of data presentation, prompted the implementation of corrective actions through innovation in instructional strategies. The aim of this Classroom Action Research (CAR) was to optimize student learning outcomes through the application of the Problem-Based Learning (PBL) approach, which focused on increasing student engagement during teaching and learning activities. This method was chosen for its potential to stimulate active participation, sharpen logical thinking skills, and encourage students to face and solve problems that reflect real-life situations. Through this strategy, students were expected to develop an understanding of data presentation concepts and demonstrate improvements in both academic achievement and classroom engagement. The study involved 28 fifth-grade students from SD Negeri 1 Banjar Anyar, with data collection techniques including interviews, tests, observations, and documentation. Data validity was ensured through technique and source triangulation, and the data were analyzed both qualitatively and quantitatively. The research was conducted over two cycles. In Cycle I, the average student score was 78.75 with a mastery level of 64.3%. After improvements in Cycle II, the average score increased to 89.64, with a mastery level reaching 96.4%. These outcomes surpassed the Minimum Mastery Criteria (KKM), which set an average score of 70 and a classical completeness threshold of 80%. The implementation of PBL had a positive impact on improving mathematics learning outcomes, particularly in the topic of data presentation. Keywords: learning outcomes, data presentation, PBL]]>
