Tujuan penelitian adalah: 1) mengembangkan modul berbasis Inquiry Lab, 2) menguji kelayakan modul berbasis Inquiry Lab, dan 3) menguji efektivitas modul berbasis Inquiry Lab untuk meningkatkan hasil belajar siswa pada materi sistem gerak di SMA Negeri 1 Mejayan. Pengembangan modul berbasis Inquiry Lab mengacu pada 9 langkah model Research and Development (R&D) dari Borg & Gall (1983) meliputi: 1) penelitian dan pengumpulan data, 2) perencanaan, 3) pengembangan produk, 4) uji coba produk awal, 5) revisi produk I, 6) uji coba lapangan, 7) revisi produk II, 8) uji coba lapangan operasional, 9) revisi produk akhir. Hasil penelitian menunjukkan: 1) modul biologi Inquiry Lab pada materi sistem gerak yang dikembangkan menggunakan sintak Inquiry Lab (observasi, manipulasi, generalisasi, verifikasi, dan aplikasi); 2) kelayakan modul berbasis Inquiry Lab sebagai berikut: a) uji validasi ahli materi 93,00%, b) validasi ahli pengembangan desain 82,90%, c) validasi ahli perangkat 95,70%, d) validator praktisi (guru) 94,00%, dan e) uji kelompok kecil 83,82%; dan 3) modul berbasis Inquiry Lab pada materi sistem gerak efektif dalam meningkatkan hasil belajar siswa (Sig.=0,000 < α=0,05). This research aimed: 1) to develop an inquiry-based laboratory module, 2) to test the feasibility of an inquiry-based laboratory module, and 3) to test the effectiveness of an inquiry-based laboratory module to improve studentsâ outcomes on motion system material at class XI of State Senior High School (SMAN) 1 of Mejayan. The development of an inquiry-based laboratory module referred to nine steps of Research and Development (R&D) model from Borg & Gall (1983) that included: 1) research and data collection, 2) planning, 3) product development, 4) initial product test, 5) product revision I, 6) field test, 7) product revision II, 8) operational field test, 9) final product revision. The research results showed: 1) the developed inquiry-based laboratory module on motion system material used the Inquiry Lab syntax (observation, manipulation, generalization, verification, and application), 2) the feasibility of an inquiry-based laboratory module as followed: a) the validation test of material expert at 93.00%, b) the validation of design development expert at 82.90%, c) the validation of tool expert at 95.70%, d) the validation of practitioners (teachers) at 94.00%, and e) the test of small group at 83.82%; and 3) an inquiry-based laboratory module on motion system material was effective to improve studentsâ outcomes (Sig.=0.000 < α=0.05).