Familiarize yourself with the relative weight of the various tests and assignments in your course. Some assignments will constitute a more significant portion of your grade than others. Usually, an instructor will make such weighting very clear at the beginning of a course or on a syllabus. If this is not clear, make sure to inquire about it.
Group your work according to the categories by which the instructor will weight and calculate your grade.
Total the number of points in each category and divide by the number of assignments in each category.
For example, if your homework grades are 74, 93, 84, and 89:
74 + 93 + 84 + 89 = 340
340/4 = 85
Multiply the overall average grade from each category by the decimal equivalent of its weighted percent.
For example, if homework is to constitute 20 percent of your final grade:
(85) * (0.20) = 17
In this case, 17 points of your final grade would be attributable to your homework.
Add all of the results from each category together. This is your final grade.
For example, if 17 points come from homework, 20 come from attendance, 38 come from tests, and 13 come from quizzes:
17 + 20 + 38 + 13 = 88
In this case, your final grade would be 88.