The purpose of this study is to describe the practicality of the mushroom material e-handout which was developed to train students' critical thinking skills. This study uses the R&D method with the ADDIE model. The stages of the ADDIE development model are carried out through 5 stages, namely Analyze, Design, Development, Implementation, and Evaluation. The e-handout is written in a communicative language, equipped with pictures and illustrations that can attract students and contain critical learning activities. Small group test subjects were conducted on 9 students and field tests were conducted on 25 students. Data obtained from practicality instruments were analyzed descriptively. The results of student responses got a value of 90% with the criteria of strongly agreeing and the results of the implementation of 84% with very good criteria. This shows that the developed e-handout is practical for developing critical thinking skills.