The research aims to describe students' thinking skills in the guided discovery learning model assisted by PhET media. The design used is a quasi-experimental: Posttest only control group design. The population in this study were all students of class XI SMA Negeri 2 Koto Kampar Hulu Academic Year 2021/2022 with a sample of 52 students consisting of class XI MIPA 1 as an experimental class tota…