One thing that you'll need to know is what is the GPA scale. You'll also need to identify whether these classes are "normal" classes, "honors" classes, or Advanced Placement classes. Also, it would be helpful to know what precisely you mean by "points." Do you mean "credits"?
Also, we need to know whether your GPA be based on a four-point scale, five-point scale, six-point scale, or what? Without knowing what the basis for the GPA is or what type of classes you are taking (normal, honors, AP), it is may be difficult to determine what the GPA is. I'm going to assume, though, that this is on a four-point scale and that by "points" you actually mean "credits."
If my assumptions are correct, here's my shot at calculating your GPA. Perhaps this will give you some idea of how to calculate this.
First, I converted your grades to a standard four-point scale used by many colleges (A = 4.0 points, A- = 3.67 points, B = 3 points, C = 2 points)
Next, I multiplied the converted number by the number of credits for each class (e.g., 3.67 x 5 = 18.35; 2 x 6 = 12; etc.) and added up these numbers.
Then, I added up your total number of credits.
5 + 6 + 6 + 4 + 6 + 6 + 4 = 37
Then, I divided the total from the grades by the total number of credits.
124.39 points / 37 credits = 3.36 GPA
Of course, this is just a ball-park figure. Your GPA may be higher depending on how many grade points your school assigns for different courses and four different grades.