A student's grade-point average, or GPA, is a measure of her performance in the classroom. A GPA can determine a student's eligibility for an athletic team and other extracurricular activities. The figure is one of the criteria used for determining admittance into a college or university. While a GPA involves simple math computations, it carries great weight and significance for a student's future.

Understand the terminology. A semester grade-point average includes classes for the current semester only. A cumulative grade-point average accounts for a student's entire career, either high school or college. A cumulative grade-point average includes all of a student's grades to arrive at an overall average; it is the number referred to when asked for a grade-point average.

Assign each letter grade a number. Most GPAs are based on a 4.0 system. If this is true, follow these assignments for numbers: A = 4 points, B = 3 points, C = 2 points, D = 1 point and F = 0 points.

Complete the math computations. Multiply the number of semester hours for a course by the grade received. For example, if a student took a 3-hour course and received a B, the multiplication would be 3 x 3 = 9. Add the total points and divide by the number of semester hours attempted.

Follow the example to find the grade-point average. A student has taken four 3-hour classes during one semester for a total of 12 semester hours. The grades for these classes are: A, B, C and F. Calculate the math to determine the points: 4 x 3 = 12, 3 x 3 = 9, 2 x 3 = 6, and 0 x 3 = 0. Add the following: 12 + 9 + 6 + 0 = 27. A student received 27 grade points for a semester. Divide 27 by 12, which is the number of hours taken for the semester. This equals 2.25 and is the student's GPA.