The introduction of the Next Generation Science Standards led many states, schools, and districts to change curricula, instruction, and professional development to align with the standards. Therefore existing assessmentswhatever their purposecannot be used to measure the full range of activities and interactions happening in science classrooms that have adapted to these ideas because they were not designed to do so. Seeing Students Learn Science is meant to help educators improve their understanding of how students learn science and guide the adaptation of their instruction and approach to assessment. It includes examples of innovative assessment formats, ways to embed assessments in engaging classroom activities, and ideas for interpreting and using novel kinds of assessment information. It provides ideas and questions educators can use to reflect on what they can adapt right away and what they can work toward more gradually.