<![CDATA[Concern for environmental cleanliness in schools is an essential aspect of character formation amid increasing environmental issues in modern education. This study aims to describe the process of internalizing the “Jumat Bersih” (Clean Friday) program in fostering students’ environmental care character and to identify the supporting and inhibiting factors in its implementation at SMA Negeri 12 Medan. This research employed a qualitative descriptive approach. Data were collected through observation, interviews, and documentation, and analyzed through data reduction, data presentation, and conclusion drawing. The results indicate that the internalization process of the Clean Friday program takes place through three main stages: habituation, exemplary behavior, and the strengthening of school culture. The activity has become a routine that cultivates students’ awareness and responsibility for maintaining school cleanliness. The supporting factors include strong leadership and teacher involvement, cooperation among school members, availability of cleaning facilities, and an award system that motivates students. Meanwhile, the inhibiting factors consist of a lack of student awareness, limited family support, insufficient facilities and time, the school’s geographical condition which is prone to flooding, and inadequate supervision. Overall, the Clean Friday program at SMA Negeri 12 Medan has proven to be an effective medium for developing students’ environmental care character through continuous and school-integrated practices. ABSTRAKKepedulian terhadap kebersihan lingkungan sekolah merupakan bagian penting dari pembentukan karakter siswa di era modern yang sarat dengan isu lingkungan. Penelitian ini bertujuan untuk mendeskripsikan proses internalisasi program Jumat Bersih dalam pembinaan karakter peduli lingkungan serta mengidentifikasi faktor-faktor pendukung dan penghambat pelaksanaannya di SMA Negeri 12 Medan. Penelitian ini menggunakan pendekatan kualitatif dengan metode deskriptif. Data diperoleh melalui observasi, wawancara, dan dokumentasi, kemudian dianalisis melalui reduksi data, penyajian data, dan penarikan kesimpulan. Hasil penelitian menunjukkan bahwa proses internalisasi program Jumat Bersih berlangsung melalui tiga tahap utama, yaitu pembiasaan, keteladanan, dan penguatan budaya sekolah. Kegiatan Jumat Bersih telah menjadi rutinitas yang membentuk kesadaran siswa untuk menjaga kebersihan dan tanggung jawab terhadap lingkungan sekolah. Faktor pendukung yang berperan dalam keberhasilan program meliputi dukungan kepala sekolah dan guru, kerja sama antarwarga sekolah, ketersediaan sarana kebersihan, serta adanya sistem penghargaan yang memotivasi siswa. Adapun faktor penghambatnya antara lain kurangnya kesadaran sebagian siswa, pengaruh lingkungan keluarga, keterbatasan waktu dan sarana kebersihan, kondisi geografis sekolah yang rawan banjir, serta kurangnya pengawasan berkelanjutan. Secara keseluruhan, program Jumat Bersih di SMA Negeri 12 Medan terbukti efektif sebagai sarana pembinaan karakter peduli lingkungan melalui kegiatan nyata yang berkelanjutan dan terintegrasi dalam budaya sekolah.]]>
