This study was motivated by the low mathematics learning outcomes of second-grade students at SD Negeri 077 Panyabungan on addition and subtraction material, where an initial observation showed that only 4 of 12 students (33.33%) met the Learning Objective Achievement Criteria (KKTP). This study aimed to describe the implementation of the Papan Jurang (Ravine Board) learning media and the resulting improvement in students' mathematics learning outcomes. This Classroom Action Research (CAR) applied the Kemmis and McTaggart model across two cycles, each consisting of planning, action, observation, and reflection stages. The subjects were 12 second-grade students. Data were collected through learning outcome tests and observation sheets, then analyzed descriptively using quantitative and qualitative approaches. Results showed that the media was implemented through concept explanation, introduction and demonstration of the media, guided student practice, and discussion of results. Student learning outcomes improved from Cycle I to Cycle II, from 7 students (58.33%) passing with a class average of 70 in Cycle I to 11 students (91.66%) passing with a class average of 90 in Cycle II, exceeding the 66% success indicator. It is concluded that the Papan Jurang media effectively improves students' mathematics learning outcomes on addition and subtraction material.