Penelitian ini bertujuan mengembangkan perangkat pembelajaran berbasis proyek untuk, (1) mengetahui tingkat kelayakan, (2) mengetahui efektivitas perangkat pembelajaran berbasis proyek, dan (3) mengetahui tingkat penguasaan keterampilan proses sains dan tingkat penguasaan materi peserta didik pada materi suhu dan kalor dengan menggunakan perangkat pembelajaran berbasis proyek. Penelitian ini merupakan penelitian pengembangan hasil modifikasi model pengembangan Borg & Gall. Hasil penelitian menunjukkan bahwa: (1) prosedur pengembangan model perangkat pembelajaran berbasis proyek mengadopsi dan memodifikasi model R & D (Borg & Gall) memperoleh nilai A dengan kategori sangat baik; (2) Efektivitas perangkat pembelajaran berbasis proyek dari guru dan observer pada aspek validitas, realibilitas, objektivitas, kepraktisan, sistematis dan Bahasa pada kategori cukup baik, dan (3) ketercapaian keterampilan proses sains peserta didik pada kelas eksperirmen mencapai 86.07% sedangkan pada kelas kontrol hanya 63.48%, Adapun penguasaan materi ditinjau dari persentase peserta didik di kelas eksperimen yang mencapai KKM sebesar 96.87% sedangkan peserta didik di kelas kontrol 6.25%. This study aims to develop project-based learning tools, (1) to determine the feasibility of the products developed; (2) determine the effectiveness of the project-based learning, and (3) determine the level of mastery of science process skills and the level of mastery of the material students in the material and the temperature of the heat by using project-based learning. This research is the development of a modified model of the development of Borg & Gall. Research activities consist of three phases: development limited, testing and expanded trials. The results show that: (1) the procedure of model development project-based learning tools adopt and modify the model of R & D (Borg & Gall) obtaining an A in the category of very good; (2) The effectiveness of project-based learning teacher and observer to the aspect of validity, reliability, objectivity, practicality, and systematic language category is average categories, and (3) The achievement of students' science process skills in the experiment reached 86.07% while in the control class it was only 63.48%. The mastery of the material based on the proportion of students in the experimental class who achieved KKM was 96.87%, while students in the control class were 6.25%.