For your number field - do a Running Total that is a distinct count of whatever identifies what you want the number to represent. In your example above, if you're translating name from some kind of ID number field, you can use that ID number. I wouldn't necessarily use "Name" because you won't get the right counts for duplicate names.
To get the extra info to disappear, right-click on the field (Grade or Name in your example), Format Field, and turn on Suppress if Duplicated.
-Dell