Here is a quick python script which calculates average, variance and standard deviation. This is also part of codeacademy work. I must say last time I worked with variance and standard deviation it was more than 10 years ago in statistics course. Hence a bit of reminder here for me too: (Some are from wikipedia and mathsisfun.com)

**Average:** In mathematics and statistics, it is called arithmetic mean according to wikipedia but simply it is the sum of a list of numbers divided by the number of numbers in the list.

**Variance:** The average of the squared differences from the mean. Here is the formula which we will use in our python code.

**Standard deviation:** Square root of the variance is the standard deviation which just means **how far we are from the normal(mean)**

Now here is the code which calculates given the number of scores of students we calculate the average,variance and standard deviation.