Penelitian ini bertujuan untuk menghasilkan perangkat pembelaran model guided discovery untuk melatihkan keterampilan proses sains yang valid, praktis, dan efektif sehingga dapat mendukung kegiatan pembelajaran. Pengembangan perangkat pembelajaran dilakukan menggunakan model 4 D (dalam penelitian ini hanya sampai tahap develop) dan rancangan uji coba One Group Pretest and Posttest Design. Kegiatan persiapan dilakukan di Pascasarjana, UNESA sedangkan uji coba pada 84 siswa kelas XI MIPA 4, XI MIPA 5, dan XI MIPA 6 dilaksanakan di SMA Negeri 1 Kedungwaru, Tulungagung. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah validasi, observasi, tes, dan angket. Hasil penelitian menunjukkan bahwa 1. validitas Silabus, RPP, Buku Ajar Siswa, Lembar Kerja Siswa, dan Tes Keterampilan Proses Sains tergolong valid 2. kepraktisan perangkat pembelajaran berdasarkan keterlaksanaan pembelajaran berkategori sangat baik dan aktivitas siswa dalam pembelajaran berpusat pada siswa (student center) 3. keefektifan perangkat pembelajaran yang digunakan dikategorikan efektif berdasarkan ketuntasan keterampilan proses sains siswa kelas XI MIPA 4 sebesar 92,86 persen, siswa kelas XI MIPA 5 sebesar 92,59 persen, dan siswa kelas XI MIPA 6 sebesar 93,10 persen serta mayoritas siswa memberikan respon positif terhadap proses pembelajaran yang dikembangkan. Berdasarkan hasil penelitian dapat disimpulkan bahwa pengembangan perangkat pembelajaran model guided discovery layak digunakan untuk melatihkan keterampilan proses sains siswa pada materi getaran harmonis sederhana.

Kata-kata kunci Perangkat pembelajaran, guided discovery, keterampilan proses sains, getaran harmonis sederhana.

This research aims to produce valid, practical, and effective the guided discovery models to train science process skills so that they can support learning activities. The learning materials was developed using 4 D models (in this research until the develop stage) and using One Group Pretest and Posttest Design to obtain the data improvement of students learning outcomes. Preparatory activities were carried out at Postgraduate, UNESA while trials on 84 students of class XI MIPA 4, XI MIPA 5, and XI MIPA 6 were conducted at SMA Negeri 1 Kedungwaru, Tulungagung. Data collection techniques used in this study were validation, observation, tests, and questionnaires. The results showed that 1. the validity of the Syllabus, RPP, Student Textbooks, Student Worksheets, and Science Process Skill Tests 2. the practicality of learning materials based on the implementation of learning categorized as very good and student activities in student centered learning 3. the effectiveness of the learning materials used are categorized as effective based on completing the science process skills of students in class XI MIPA 4 by 92.86 percent, students of class XI MIPA 5 by 92.59 percent, and students of class XI MIPA 6 by 93.10 percent and the majority of students respond positively to the learning process developed. Based on the results of the study it can be concluded that the development of guided discovery learning models is appropriate to be used to train students science process skills in simple harmonic vibration material.

Key words Teaching materials, guided discovery, science process skills, simple harmonic vibration.