Based on observations made at primary elementary schools in Ponorogo District, learning activities are still centered on the teacher and don't involve students directly. Interactive media is needed to engage students actively in learning. The purpose of this research is to develop an interactive Undeercover game medias solar system material that is feasible based on validity, practicality, and effectiveness of the media. So as to improve student learning outcomes make students easier to understand the material.

This research is a type of Research and Development (R&D) research using the Borg and Gall model that has been adapted by Sugiyono. This study limits only eight stages namely, potential and problems, data collection, product design, design validation, product revisions, product trials, product revisions, and trial use. Product trial design using one group pretest-posttest.

The validity of the media is known from the validation of the media which obtained a percentage of 90% with very valid criteria, and material validation by 91.7% with very valid criteria. Practicality is known from the results of student responses obtained a percentage of 92.8% with very practical criteria, and the results of teacher responses by 89.1% with very practical criteria on product trials. Then in the trial use, the results of student responses obtained a percentage of 93.6% with very practical criteria and the results of teacher responses by 94.5% with very practical criteria. The effectiveness of the media is known from the percentage of students' mastery learning by 90.3% with very good criteria, and N-Gain obtained a score of 0.73 with high criteria. So, the Undeercover game medias solar system material is feasible to use.