Last modified: 2023-12-10

#### Abstract

**ABSTRACT**** **

This study aimed at finding out the effectiveness of Cooperative Learning Type *Student Teams Achievement Division *(STAD for the mathematics learning outcome at class XI MIPA 1 of SMA Negeri 1 Nosu. This type of research is quantitative research in the form of a *pre-experimental* design with one group pretest posttest. The population of this study was all class XI SMA Negeri 1 Nosu where the sample was class XI MIPA 1. The data analysis technique used in this study was descriptive analysis, gain test and inferential statistics at a significant level of 0.05 through the SPSS program version 25. Based on the results of the descriptive analysis, the mean score of pretest was 42.41 with a standard deviation of 8.0158 and the mean score of posttest was 80.14 with a standard deviation of 7.7723. Based on the normality test after treatment, it was found ᵡ^{2}_{count} = 9.909 and ᵡ^{2}_{table} = 21.026. Because the value of ᵡ^{2}_{count} ˂ ᵡ^{2}_{table} means that the scores of students' mathematics learning outcomes are normally distributed. While the t- test obtained was tcount = 7.324 and ttable = 1.72. Since, t_{count} ˃ t_{table} is obtained, H_{0} is rejected and H_{1} is accepted. It means that students’ mathematics learning outcome is higher than the KKM. Likewise, by using the gain test formula, the gain value is 0.66 and is in the medium category. Thus, it can be concluded that the cooperative learning type *Student Teams Achievement Division* (STAD) is effective on students’ mathematics learning outcomes at class XI MIPA 1 of SMA Negeri 1 Nosu.

**Keywords**: Effectiveness, Cooperative Learning, STAD, Mathematics Learning Outcome