摘要：Penelitian ini bertujuan untuk: (1) menghasilkan Lembar Kerja Peserta Didik (LKPD) kimia berbasis inkuiri terbimbing yang layak untuk peserta didik kelas XI IPA SMA, (2) mengetahui kepraktisan LKPD berbasis inkuiri terbimbing, dan (3) mengetahui keefektifan LKPD berbasis inkuiri terbimbing. Penelitian ini merupakan penelitian dan pengembangan yang menggunakan model Thiagarajan. Prosedur pengembangan meliputi tahap pendefinisian, perancangan, dan pengembangan. Tahap pendefinisian dilakukan survei untuk menganalisis permasalahan dan kebutuhan peserta didik. Tahap perancangan disesuaikan dengan kebutuhan dalam kegiatan pembelajaran. Tahap pengembangan dilakukan validasi ahli materi dan media kemudian diimplementasikan di kelas XI IPA SMAN 2 Wates pada 20 peserta didik. Hasil penelitian menunjukkan bahwa: (1) Hasil validasi LKPD kimia yang dikembangkan dikategorikan layak berdasarkan hasil validasi ahli materi dengan rerata skor 3,8 dan ahli media dengan rerata skor 4,0, (2) tingkat kepraktisan LKPD berada dalam kategori sangat baik, dan (3) keefektifan LKPD memperoleh sig < 0,05 membuktikan ada perbedaan yang signifikan antara kelas eksperimen dan kontrol. Kata Kunci : lembar kerja peserta didik, kimia, inkuiri terbimbing DEVELOPING CHEMISTRY WORKSHEETS BASED ON GUIDED INQUIRY FOR THE SECOND GRADE STUDENTS OF SENIOR HIGH SCHOOL Abstract This research study aims to: (1) produce valid chemistry worksheets based on guided inquiry for the second grade students of senior high school, (2) know the practically of worksheets based on guided inquiry, and (3) know the effectiveness of worksheets based on guided inquiry. This study was research and development using the Thiagarajan model. The procedure of the development included the steps of defining, designing, and developing. In the defining step, a survey to analyze the problems and student’s needs. The designing step, was conducted the needs of the learning activities. The development step a validation was done by materials and media experts then implementation in class XI science of SMAN 2 Wates to 20 students. The result of the study shows: (1) the chemistry worksheets produced fullfills the appropriateness criteria based on the result of materials experts with the mean score 3.8 and media experts is 4.0 which is in a good category, (2) the practically level is in the very good category, and (3) the effectiveness of worksheets obtaining sig < 0.05 proves there is a significant difference between the experimental and control class.
