Ok, so I'm trying this, and I keep getting an error, I think when codeacademy tries to substitute other values as a test.

This is where I'm failing.

Oops, try again. grades_variance([7, 0, 1, 8, 5, 2, 6, 3, 7]) returned 5797.2046351085 instead of the expected: 7.5555555556

When I run it for grades I get the right values, is there some way to bypass this extra test, or is my code just wrong somewhere? I look at a number of other responses and the codes seems right.

I think the site is broken? If I add the set of numbers from the error into the grades list the variance itself works fine but I get a different error then:

Oops, try again. grades should contain [100, 100, 90, 40, 80, 100, 85, 70, 90, 65, 90, 85, 50.5]!

Any ideas of what I might be doing wrong would be appreciated.

```
grades = [100, 100, 90, 40, 80, 100, 85, 70, 90, 65, 90, 85, 50.5]
#grades = [9, 1, 7, 5, 6, 2, 9, 3]
def print_grades(grades):
for grade in grades:
print grade
def grades_sum(grades):
total = 0
for grade in grades:
total += grade
return total
def grades_average(grades):
sum_of_grades = grades_sum(grades)
average = sum_of_grades / float(len(grades))
return average
def grades_variance(scores):
num = len(scores)
average = grades_average(grades)
variance = 0
for score in scores:
variance += float(average - score) ** 2
return variance/num
print grades_variance(grades)
```