A normal curve graph represents the mathematical model of a distribution of normally distributed standard scores with a mean equal to zero (0) and a standard deviation equal to one (1.0). This normal curve graph displays the 100 meter times for boys and girls at a high school in Hawaii. Obviously, the school must have some excellent sprinters based on the times. The value of a normal curve is that it allows you to compare the position of an individual value relative to the distribution as a whole and against a "normal" set of data.