Obtain your letter grades from each teacher. Your letter grades are given a numerical value that is used to calculate your grade point average. Every "A" is worth four points, every "B" worth three points, every "C" worth two points, every "D" worth one point, and every "F" has no value.
Figure out the numerical value given to each letter grade you have received. Now calculate the total of all of your grades. For example, if you have eight classes and you have an "A" in all eight and "A" is equal to four points, you have 32 points.
Use division on the final step of calculating your GPA. Divide the total number of points you have into the number of classes you are taking. For example, you will divide 32 into eight to come up with 4.0, which is your grade point average, and the highest you can obtain.