Penelitian ini bertujuan untuk menghasilkan modul berbasis saintifik sebagai bahan ajar pada pembelajaran ipa materi pokok sistem peredaran darah manusia untuk siswa kelas viii smp/mts yang berkualitas dari segi kelayakan dan kepraktisan. penelitian ini merupakan penelitian research and development (r&d) dengan menggunakan model borg and gall (1983) yang terdiri 10 langkah yaitu 1) penelitian dan pengumpulan informasi, 2) perencanaan, 3) pengembangan produk awal, 4) uji lapangan awal, 5) revisi produk utama, 6) uji lapangan utama, 7) revisi produk operasional, 8) uji lapangan operasional, 9) revisi produk akhir, 10) desiminasi dan implementasi. namun, penelitian ini hanya sampai pada tahap ketujuh, yaitu tahap revisi produk operasional karena keterbatasan peneliti. data peneliti dianalisis melalui uji kelayakan dan uji kepraktisan. uji kelayakan dilakukan oleh validator ahli media, ahli materi, dan praktisi (guru ipa). uji kepraktisan dilakukan oleh respon guru, respon siswa, dan observer keterpakaian produk. uji lapangan awal dilakukan di smp negeri 10 tarakan pada kelas viii-1 sebanyak 10 siswa. uji lapangan utama dilakukan di smp negeri 10 tarakan pada kelas viii-1 sebanyak 30 siswa. hasil validasi diperoleh dari ahli media sebesar 86,67% dengan katagori sangat layak, ahli materi sebesar 87,61% dengan katagori sangat layak, praktisi guru ipa sebesar 86,31% dengan katagori sangat layak. hasil kepraktisan diperoleh dari respon guru ipa sebesar 86,11% dengan katagori sangat praktis, respon siswa sebanyak 10 siswa sebesar 93,89% dengan katagori sangat baik, respon siswa sebanyak 30 siswa sebesar 89,75% dengan katagori sangat baik, observasi keterpakaian produk sebesar 92,85% dengan katagori sangat praktis. berdasarkan hasil penelitian, dapat disimpulkan bahwa modul berbasis saintifik layak dan praktis untuk digunakan dalam pembelajaran ipa di sekolah.

This research conducted with research and development (r&d) by using borg and gall model (1983) that consists of 10 step, such as 1) research and information collecting, 2) planning, 3) develop preliminary from of product, 4) preliminary field testing, 5) main product revision, 6) main field testing, 7) operational product revision, 8) operational field testing, 9) final product revision, 10) dissemination and implementation. this research only until seventh step, which is revised operational product because the research limitations. the data will conduct by standard test and practicality test. the data researchers have been analyzed through the fit and proper test and test it practicality .the fit and proper test was carried out by validator media experts , the people of the material , and practitioners (science teacher). the feasibility test is performed by a media expert's, material expert, and practitioner (ipa teacher). practical testing is done by teacher response, student response, and observer of product usage. initial field test was conducted at smp negeri 10 tarakan in class viii-1 as many as 10 students. the main field test was conducted at smp negeri 10 tarakan in grade viii-1 as many as 30 students. validation results obtained from media experts amounted to 86,67% with very decent category, material experts of 87,61% with very reasonable category, practitioners of 86,31% with the category very feasible. practical results obtained from the response of science teachers amounted to 86,11% with very practical categories, students' responses as many as 10 students of 93,89% with very good category, student responses as many as 30 students of 89,75% with very good category, observation of product usage amounting to 92,85% with very practical category. based on the results of the study, it can be concluded that scientificbased modules are feasible and practical for use in science learning at schools.