Putra Risal Marcelino Nope Pengarang SEMUEL HAJAI NITBANI Dosen Pembimbing 1 Margareta P.E.Djokaho,S.Sn.M.Pd. Dosen Pembimbing 2 Dian Sari Arindah Pekuwali Ketua Penguji

Thesis by Putra Risal Marcelino Nope (2101010078), titled “The Effectiveness of the Application of the Cooperative Learning Model Two Stay Two Stray in Teaching Observation Report Texts to Grade X Students of SMA Negeri Usapimnasi.” Supervised by Drs. Semuel H. Nitbani, M.Pd and Margareta P. E Djokaho, S.Sn., M.Pd. The research problem is: how effective is the application of the cooperative learning model Two Stay Two Stray in teaching observation report texts to Grade X students of SMA Negeri Usapimnasi? This study is a Classroom Action Research with four stages: planning, action, observation, and reflection. Data was collected through observation, tests, and documentation. Research results show that in the implementation of Cycle I, out of 32 students, 21 students (65.62%) achieved mastery, meeting the criteria of actively participating in class, engaging in group discussions, correctly answering test questions, and quickly adapting to the Two Stay Two Stray learning model. Meanwhile, 11 students (34.37%) did not achieve mastery due to poor participation in class, lack of group discussion involvement, low test scores, and limited understanding of the Two Stay Two Stray method. In Cycle II, 28 out of 32 students (87.5%) achieved mastery, while 4 students (12.5%) did not, due to similar factors: poor classroom participation, lack of group engagement, low test performance, and absenteeism. Based on these results, it can be concluded that the application of the cooperative learning model Two Stay Two Stray in teaching observation report texts can improve the learning outcomes of Grade X students at SMA Negeri Usapimnasi. Keywords: Cooperative, Two Stay Two Stray, Observation Report