AbstrakPenelitian ini bertujuan untukmengetahui sejauhmana keberhasilan penyelenggaraan lima hari sekolah di SMA Negeri 1 Ngemplak yang meliputi proses, kesiapan dan hambatan yang muncul.Penelitian ini termasuk jenis penelitian evaluatif deskriptif dengan menggunakan model CIPP (context, Input, Process, Product) dari Stuflebeam. Subyek penelitian adalah warga sekolah, terdiri dari 370 siswa, 27 guru dan 7TU. Metode pengambilan data dengan angket, wawancara, dokumentasi dan observasi. Data dianalisis dengan menggunakan teknik analisis deskriptif.Hasil penelitian menunjukkan: Penyelenggaraan lima hari sekolah di SMA Negeri 1 Ngemplak tergolong berhasil, dengan rata-rata perolehan skor sebesar 2,87. Ditinjau dari dimensi kontek, input dan proses termasuk berhasil dengan rata-rata perolehan skor masing-masing sebesar 3,01, 2,84, dan 2,95. Sedangkan pada dimensi produk termasuk dalam kategori cukup, dengan rata-rata skor yang diperoleh sebesar 2,68. Hambatan selama proses penyelenggaraan lima hari sekolah berupa jumlah kantin dan staf TU belum mencukupi, serta guru yang belum bisa membawakan pembelajaran dengan kreatif dan menarik, sehingga berdampak pada kondisi fisik dan psikis siswa berupa rasa bosan, letih dan mengantuk. AbstractThis study aims to determine the extent of the successful implementation of five school days in Ngemplak 1 Senior High School which includes the processes, readiness and obstacles that arise.This study belongs to the category of descriptive evaluative research using evaluation model of CIPP (context, Input, Process, Product).The study was conducted at Ngemplak 1 Senior High School which has 370 students, 27 teachers and 7 staffs. Data was taken using techniques: questionnaires, interviews, documentation and observation. The research data was then analyzed using descriptive analysis techniques.The results of this study showed that the holding of five school was successful, with an average score of 2.87. Judging from the dimensions of the context, inputs and processes including the successful category with an average score of 3.01, 2.84, and 2.95 respectively. While the dimensions of the product are included in the sufficient category, with an average score of 2.68. Obstacles during the process of organizing five school days in the form of the number of canteens and education personnel that are still insufficient, and teachers who have not been able to bring learning creatively and attractively, which have an impact on both students' psychic and physical such as boredom, fatigue and sleepiness.