<![CDATA[Abstract: The quality of teachers' instruction is a key determinant of educational success; however, academic supervision instruments used in schools are often general, administrative, and insufficiently aligned with local needs. This study aimed to develop and examine the effectiveness of an academic supervision instrument for measuring the instructional quality of junior high school teachers in Selayar Islands Regency. The study employed a Research and Development approach adapted from the Borg and Gall model, involving needs analysis, document review, instrument drafting, focus group discussion, expert validation, limited trial, wider trial, and finalization. The trials involved 50 teachers in the limited stage and 100 teachers in the wider stage. The resulting instrument consisted of 78 items covering lesson planning, instructional implementation, and learning assessment/follow-up. The findings showed that the instrument met the criteria of validity, reliability, practicality, and effectiveness. Its internal reliability was very high, with Cronbach's Alpha coefficients of 0.992 in the limited trial and 0.994 in the wider trial. The effectiveness test indicated a very strong relationship between academic supervision scores and directly observed instructional quality. Therefore, the instrument is feasible for measuring the instructional quality of junior high school teachers objectively, systematically, practically, and contextually in island-based educational settings. Keywords: instructional quality; academic supervision; supervision instrument; junior high school teachers; Selayar Islands Abstrak: Kualitas pembelajaran guru merupakan faktor penting dalam menentukan keberhasilan pendidikan, tetapi pengukurannya sering belum objektif karena instrumen supervisi akademik yang digunakan masih bersifat umum, administratif, dan belum sepenuhnya sesuai dengan kebutuhan sekolah. Penelitian ini bertujuan mengembangkan dan menguji efektivitas instrumen supervisi akademik untuk mengukur kualitas pembelajaran guru SMP di Kabupaten Kepulauan Selayar. Penelitian menggunakan pendekatan Research and Development yang diadaptasi dari model Borg dan Gall melalui tahapan analisis kebutuhan, kajian dokumen, penyusunan draf instrumen, Focus Group Discussion, validasi ahli, uji coba terbatas, uji coba luas, revisi, dan finalisasi produk. Uji coba terbatas melibatkan 50 guru, sedangkan uji coba luas melibatkan 100 guru SMP. Instrumen yang dihasilkan terdiri atas 78 butir, mencakup 30 butir perencanaan pembelajaran, 31 butir pelaksanaan pembelajaran, dan 17 butir penilaian serta tindak lanjut pembelajaran. Hasil penelitian menunjukkan bahwa instrumen memenuhi kriteria validitas, reliabilitas, kepraktisan, dan efektivitas. Reliabilitas internal berada pada kategori sangat tinggi dengan nilai Alpha Cronbach 0,992 pada uji terbatas dan 0,994 pada uji luas. Efektivitas instrumen ditunjukkan oleh hubungan sangat kuat antara skor supervisi akademik dan kualitas pembelajaran yang diamati langsung. Dengan demikian, instrumen supervisi akademik ini layak digunakan sebagai alat ukur kualitas pembelajaran guru SMP secara objektif, sistematis, praktis, dan kontekstual di wilayah kepulauan. Kata Kunci: kualitas pembelajaran; supervisi akademik; instrumen supervisi; guru SMP; Kepulauan Selayar ]]>
