EFEKTIVITAS PENERAPAN MODEL COOPERATIVE LEARNING DALAM MENINGKATKAN PENGUASAAN KOSAKATA BAHASA ARAB SISWA PONDOK MODERN DARUL ISLAM LAMONGAN

This study aims to describe students' Arabic vocabulary mastery prior to the application of the Cooperative Learning model, to describe the implementation process, and to examine the model's effectiveness in improving students' vocabulary mastery. This research uses a quantitative approach with a quasi experimental design with a non-equivalent control group design. The research sample consists of 40 students divided into experimental and control classes. Data were collected through observation, interviews, and tests (pre-test and post-test). Data analysis was conducted using SPSS (Statistical Product and Service Solutions) with validity tests, reliability tests, normality tests, paired sample T-tests, and effectiveness tests. The results indicate that the students' initial ability was in the low category, with an average score of 47.25. The implementation of the STAD model was carried out through heterogeneous group work and individual quizzes that encouraged active interaction. The STAD model proved effective in improving Arabic vocabulary mastery. This is evidenced by the post-test average score of 80.00 and an N-Gain value of 62.44% (moderately effective). Thus, the STAD model can be an innovative solution to enhance the quality of Arabic language learning in the pesantren (Islamic boarding school) environment.