The aims of this study was to develop of teaching materials IPA SMP using discovery learning models on global warming to improve student learning outcomes. Research method used in this experiment was R&D (Research and Development). Teaching materials developed included syllabi, lesson plans, student’s book, student’s worksheets, and student assessment (knowledge). The study was conducted a limited trial in SMP Negeri 2 Kebomas, Gresik using one group pre-test and post-test design. feasibility of teaching materials was studied from the aspect of validity, practicality and effectiveness. The results of reaserch showed feasibility study of the aspect of validity in terms of the results of the validation by experts and practitioners obtained average 89.06% with very good category and 96.87% have good readability. The feasibility study on the practicality aspect implementation showed that an average of 86.3% with very good category and is supported by the discovery activities of the students raised in learning. The feasibility of the effectiveness aspect of student learning results obtained realm attitudes and skills 100% complete and average domain knowledge is 3,2 to 100% of students increased learning outcomes as well as 93% of students give positive response to the discovery learning. It can be concluded that the discovery learning model learning device worthy of the aspect of validity, practicability and effectiveness and can improve student learning outcomes. Keywords: Effectiveness, Learning Materials, Learning Outcomes,Ppracticability, Validity.