The Effect of The Student Facilitator and Explaining Cooperative Learning Model on The Mathematical Problem-Solving Ability of Grade IX Students at Junior High School Tiga Hati Kepenuhan Hulu

This study aims to determine the effect of the cooperative learning model, Student Facilitator and Explaining, on students' mathematical problem-solving abilities in Grade IX of SMP Tiga Hati Kepenuhan Hulu. The research employed a quantitative approach with a quasi-experimental design. The study subjects were Grade IX students divided into two groups: the experimental group, which was taught using the Student Facilitator and Explaining model, and the control group, which was trained using a conventional learning model. Data were collected through a mathematical problem-solving ability test. The hypothesis testing results showed that the t-value (2.37) was greater than the t-table value (2.12) at a significance level of α = 0.05. Therefore, H₀ was rejected and H₁ was accepted. This indicates a significant effect of the Student Facilitator and Explaining cooperative learning model on students’ mathematical problem-solving abilities