I assume you are talking about:

```js
    var gradeLevels = $('#predictor-course-grade').data('grade-levels');
    var grade, level;
    if(gradeLevels.length){
      gradeLevels.every(function(element, index){
        grade = gradeLevels[index][1];
        level = gradeLevels[index][2];
        return gradeLevels.length > (index+1) && scoreTotal >= gradeLevels[index+1][0] && scoreTotal >= 0
      })
    }
```
In which case, here's what I'm trying to do:

scoreTotal is the total amount of points that a user has, predicted score vals + actual graded vals. 

gradeLevels is an array that looks similar to this:

```js
[[0,"F","Boop"],[600000,"D+",null],[650000,"C-",null],[700000,"C",null],[750000,"C+",null],[800000,"B-",null],[850000,"B",null],[900000,"B+",null],[950000,"A-",null],[1000000,"A",null],[1245000,"A+",null]]
```

First it check if gradeLevels is actually there, and if it is, it loops through the array.

Then it loops through the array until it hits a falsey value.
So if our current score is 500,000 for example, lets loop through the array

grade = gradeLevels[index][1] == [0,"F","Boop"][1] == "F"
level = gradeLevels[index][2] == [0,"F","Boop"][2] == "Boop"

Is there another iteration after this iteration of the array? (yes, there are 10 iterations after this one) If so, is the score greater than the first element in the next iteration? (Next iteration first element == [600000,"D+",null][0] == 600000, 500000 < 600000, so no), alright lets stop here. 

Does that make sense? It doesn't loop through all the values, just loops until it hits a case where the next iteration hits a certain condition.