Abstract :
This study aims to produce a mathematics learning tool with a Realistic Mathematics Education (RME) approach that has been tested for validity. This research is limited to the development of learning tools consisting of Learning Implementation Plans (RPP) and Student Worksheets (LKPD) with the material used is material for SMP / MTs class VIII students in learning the Pythagorean Theorem. The research model used in this study is a 4-D development model. Due to limitations caused by the COVID-19 pandemic, the development of learning devices in this study is only limited to the stages of defining, designing, and developing. Each validator gives an appropriate assessment for each aspect from RPP-1 to RPP-4 and each aspect in the RPP is found to be a total average of 87.3% and 87.8% with a very valid level of validity. Meanwhile, each validator has a nearly similar assessment for every aspect of LKPD-1 to LKPD-4 and each aspect of this LKPD has a total average of 84.7% and 84.82% with a valid validity level. The weakness of this research is that the developed device has not yet been tested.