The science learning process in junior high school has now been encouraged to give teachers more freedom in developing learning and is more flexible. Teachers need Student Worksheet which can facilitate the learning process with more flexibility regarding the material, both for material with a lot of theoretical reading and material. assignment of experimental projects and problem solving. Student Worksheet will be more optimal if it is developed with an approach that involves students thinking through Real Picture Analysis (RPA) so that students are able to generate learning motivation and enliven an interactive classroom atmosphere. RPA is an activity for students to determine interpretations and provide assessments through image media in the form of photography of science events in their environment. The aim of this research is to examine RPA-based Student Worksheet to improve junior high school students' critical thinking skills with validity. The type of research used is Research and Development research. This research and development methodology is closely related to RPA-based Student Worksheet to improve students' critical thinking skills. Validation activities through Focus Group Discussion (FGD). The development model in this research refers to the 4D (four-D) research and development model. The 4D research and development model consists of 4 main stages, namely define, design, develop and disseminate. The validation results for material substance got a percentage of 90% in the valid category, learning design got a percentage of 87% in the valid category, and the use of Student Worksheet got a percentage of 99% in the valid category. The development of RPA-based Student Worksheet considers the elements of writing, the hierarchy of material in the form of photography and the selection of questions as efficient and effective stimuli that can direct students to improve their critical thinking skills.