This study is motivated by the low mathematics learning outcomes of fifth-grade students on the topics of KPK and FPB at MI Ma’arif Budiluhur. One of the factors influencing this condition is the limited use of learning media, which results in students being less active and experiencing difficulties in understanding mathematical concepts. This study aims to determine the improvement of students’ mathematics learning outcomes through the use of the Papan Musi teaching aid. This research employed a quantitative approach with a quasi-experimental design using a nonequivalent control group design. The population consisted of all fifth-grade students at MI Ma’arif Budiluhur, totaling 67 students, with 34 students in the experimental class and 33 students in the control class. Data were collected through tests, observations, interviews, and documentation. Data analysis techniques included validity test, reliability test, normality test, homogeneity test, independent sample t-test, and N-Gain test. The results showed that the use of the Papan Musi teaching aid can improve students’ mathematics learning outcomes. This is evidenced by the average N-Gain score of the experimental class, which was 0.52 in the medium category, while the control class obtained 0.40, also in the medium category. Although both classes were in the same category, the experimental class achieved a higher N-Gain score than the control class. Therefore, it can be concluded that the use of the Papan Musi teaching aid has a positive effect on improving the mathematics learning outcomes of fifth-grade students on KPK and FPB topics.