This chapter draws upon data from an ongoing seven-year study of game-informed and game-based learning in public high school math classes in the northeastern United States. The researcher has worked closely with the same math teacher and his students to develop and refine a cooperative testing approach piloted and integrated into in the teacher's math classes since 2017. For this study, data from students' post-cooperative assessment reflections, along with hundreds of hours of classroom observation and eight student interviews, suggest that the cooperative features inherent in videogaming and esports can support a revised approach to assessing learning, one which honors social responsibility and meaningful learning.