List all of the core classes the student has taken. The exact home-school requirements vary by state, but core classes usually include English, math, science, history and foreign languages. Some states might call history "social studies" instead, depending on the state. Include any other classes in a separate list. This will allow for a weighted and an unweighted GPA. The weighted GPA includes elective classes, like art or music, with the core classes while an unweighted GPA includes only the academic classes.
Assign a letter grade to each class. Letter grades are based on the students' test scores while they take the class. For English, it might also include essays with the tests. Average the scores on the tests to find the course total average. For example, if a course had only two tests, add the scores together and divide by two for the average scores. Assign scores of 90 to 100 as an A, 80 to 89 as a B, 70 to 79 as a C, 60 to 69 as a D and anything below 60 as an F.
Write out the GPA score per class. An A is 4.00, a B is 3.00, a C is 2.00, a D is 1.00 and an F is 0.
Add all of the scores together. For example, if there are three classes with two As and one B, the answer is 11. Divide the score by the number of classes, such as 11 divided by 3. The GPA is the final answer. In the example, the GPA is 3.66.