<![CDATA[ABSTRACT Self-control is an individual's ability to regulate thoughts, emotions, and behaviors in accordance with goals and applicable norms, which plays an important role in students' academic success and social adjustment. This study was motivated by the identification of several eleventh-grade students at SMA Negeri 1 Gerung who demonstrated low self-control, as indicated by frequent lateness to class, becoming easily angry when reprimanded, noncompliance with school rules, and conflicts with peers. This study aimed to determine the effect of Rational Emotive Behavior Therapy (REBT) counseling on the self-control of eleventh-grade students. A quantitative approach with a one-group pretest-posttest design was employed. The research subjects were selected using purposive sampling based on the results of an initial assessment of self-control using a Likert-scale questionnaire. The intervention was conducted through group counseling using the REBT approach, consisting of problem identification, identification of irrational thoughts, challenging irrational beliefs, developing rational beliefs, changing emotional and behavioral responses, and practicing the acquired skills. Data were analyzed using the Shapiro-Wilk normality test and the Paired Sample t-Test with the assistance of SPSS. The results showed an increase in the mean self-control score from 103.67 in the pretest to 128.00 in the posttest. The Paired Sample t-Test yielded t = 17.541, df = 5, and p = 0.000 < 0.05. Therefore, group counseling using the REBT approach had a significant effect on improving students' self-control and can serve as an alternative guidance and counseling service in schools. ABSTRAK Kontrol diri merupakan kemampuan individu dalam mengatur pikiran, emosi, dan perilaku sesuai dengan tujuan dan norma yang berlaku, yang berperan penting dalam keberhasilan belajar dan penyesuaian sosial siswa. Penelitian ini dilatarbelakangi oleh ditemukannya siswa kelas XI SMA Negeri 1 Gerung yang menunjukkan kontrol diri rendah, ditandai dengan keterlambatan masuk kelas, mudah marah ketika ditegur, kurang mematuhi tata tertib, dan terlibat konflik dengan teman sebaya. Penelitian ini bertujuan untuk mengetahui pengaruh konseling Rational Emotive Behavior Therapy (REBT) terhadap kontrol diri siswa kelas XI. Penelitian menggunakan pendekatan kuantitatif dengan desain one-group pretest-posttest. Subjek penelitian ditentukan melalui teknik purposive sampling berdasarkan hasil pengukuran awal kontrol diri menggunakan angket berskala Likert. Perlakuan diberikan melalui konseling kelompok dengan pendekatan REBT yang meliputi identifikasi masalah, identifikasi pikiran irasional, menantang keyakinan irasional, membangun keyakinan rasional, perubahan emosi dan perilaku, serta latihan dan praktik. Data dianalisis menggunakan uji normalitas Shapiro-Wilk dan Paired Sample t-Test dengan bantuan SPSS. Hasil penelitian menunjukkan adanya peningkatan rata-rata skor kontrol diri dari 103,67 pada pretest menjadi 128,00 pada posttest. Hasil Paired Sample t-Test menunjukkan nilai t = 17,541, df = 5, dan p = 0,000 < 0,05. Dengan demikian, konseling kelompok dengan pendekatan REBT berpengaruh signifikan terhadap peningkatan kontrol diri siswa kelas XI SMA Negeri 1 Gerung dan dapat menjadi alternatif layanan Bimbingan dan Konseling di sekolah.]]>
