> In American universities where your GPA from your in-class assessments forms part of your final grade? Yes, absolutely. Whether not doing everything to maxim

> In American universities where your GPA from your in-class assessments forms part of your final grade? Yes, absolutely. Whether not doing everything to maximize your GPA is "stupid" (literally or figuratively) is a good question too. But even if your assignments influence your GPA it's rarely the only thing that does, and not doing assignments will harm your ability to perform in midterm/exam/whatever.