High schools typically use a 100point grading system. By utilizing the 100point grading system, you need to calculate the average grade using a basic averaging formula. However, it does get complicated depending on if your school weighs classes differently. For example, some schools have gym count as half a class when computing grades or have advanced placement classes, which count for more in order to encourage students to take the course without negative results.

Write out the grade you received for each class. If the class is weighted, then write the weight next to the grade. For example, assume a student gets an 96 in Math, 85 in English, and 90 in AP Statistics. AP classes are usually worth more than what a regular class is worth.

Multiply the average by any weights given to the associated classes. In the example, AP Statistics is weighted by 1.1 curve, so 90 times 1.1 equals a 99. Then gym is 88 times .5, which is 44.

Add together the average of each class. In the example, 96 plus 85 plus 99 plus 44 equals 324.

Divide by the amount of classes you took. In the example, divided by 3.5 because three classes are worth equal amounts and gym is half a class. Therefore, 324 divided by 3.5 equals an average of 92.57.
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