I just taught a course with two students taking it for graduate credit and the rest for undergraduate credit. All students were registered in the same class section, but University rules require that graduate credit have additional assignments and a different grading scheme. In this case, graduate credit included extra in-depth questions with each problem set and presentation of a topic to the class. Exam grades were also weighted differently. Canvas provides a way to assign the extra work to only selected students but no way to apply the different grading scheme.
Specifically, graduate grades were determined by 25% exams, 15% homework (with extra assignments), 10% presentation; undergraduate grades were determined by 30% exams, 10% homework.