The Effectiveness of the Problem-Based Learning Model Assisted by Flat-Sided Solid Shape Board on Students’ Mathematical Problem-Solving Ability

Abstract

This study was motivated by the low mathematical problem-solving ability of students, particularly in solving problems related to cube and cuboid topics, especially those involving surface area and volume calculations. The objectives of this research are: (1) to determine the mastery of students’ mathematical problem-solving ability, and (2) to determine the improvement of students’ mathematical problem-solving ability after being taught using the Problem-Based Learning model assisted by the flat-sided solid shape board media in the cube and cuboid material for Grade VIII students at SMP N 3 Brebes. This research is an experimental study with a One-Group Pretest-Posttest Design. The research sample was class VIII F of SMP Negeri 3 Brebes in the 2025/2026 academic year. Data collection techniques used were tests and documentation. The test instruments in this study included a pre-test and a post-test, which had been tested for validity, reliability, difficulty level, and discrimination index. Data were analyzed using prerequisite tests, namely normality and homogeneity tests, and hypothesis testing, which included a one-sided right proportion test, paired sample t-test, and N-gain score analysis. The results showed that the implementation of the Problem-Based Learning model assisted by the BRUKUBA board was effective in improving students’ mathematical problem-solving ability. This was evident from the increase in test scores before and after the treatment, as well as statistical test results that supported the effectiveness of the model and media. Therefore, this learning model and media can serve as an alternative in mathematics learning, particularly in flat-sided solid shape topics.