Critical thinking is one of the abilities that need to be given to students in 21 stcentury learning. If students do not have critical thinking ability, students will experience obstacles in achieving learning goals. Learning resources could facilitate students in enhancing critical thinking ability. This research aims to analyze and design electronic student worksheet material based on discovery learning model to enhance critical thinking ability. Electronic student worksheets are developed with the ADDIE model. The subject of this research is 8 th -grade students of Muhammadiyah 1 Pundong Junior High School. The instruments used were validation sheets, an observation guide, and an interview guide. The validation sheets were given to the material and media experts to assess the electronic student worksheet quality. Interviews were conducted towards teachers and students to gain information about the curriculum and students' characteristics. The data were analyzed through data reduction, data presentation, and conclusions were drawn. The result of this research shows that electronic student worksheet needs to be developed with regard to the discovery learning model and students' characteristics. The electronic student worksheet is designed to enhance critical thinking ability. Further research could be conducted towards the development stages, implementation, and evaluation. The results of this study can be used as a guide for mathematics teachers in developing electronic student worksheet that makes students understand mathematics and have critical thinking skills simultaneously. The novelty of this research is to integrate critical thinking skills into electronic student worksheet. In addition, electronic student worksheet is designed according to the discovery learning model.