Simulations and immersive environments provide innovative ways to measure students’ science reasoning and inquiry skills. These computer-based assessments allow for dynamic displays of science systems that expand how phenomena, information, and data can be represented; they also allow for interactivity that provides new ways for learners to demonstrate their knowledge and skills. A number of groups have been working to create and evaluate next-generation assessments that both evaluate students on 21st Century scientific skills and provide evidence models for making inferences about student proficiency. In this symposium, researchers who are currently developing and testing simulation-based and immersive assessments to meaningfully assess science content and inquiry skills will share findings from classroom-based studies of students using the assessments. The presentations will be followed by a discussion from James Pellegrino, an expert in assessment design.