How to return the student with the highest grade for their class

[alex1alex]

Hi,
Starting with this:

I'd like to end up with this in PowerBI

The calculated column for TopStudent should be something like:

=CALCULATE(FIRSTNONBLANK(Grades[Student],1),
                                    MAX(Grades[Grade],
                                    FILTER(Grades,Grades[Teacher]=Teachers[Teacher]))
                                    )

Look up the Topgrade of this rows teacher and then return the corresponding student's name.

As an aside, if I was just doing this in Excel/PowerPivot, I think I'd just do in a pivot table....but I want it in the DAX table since it's PowerBI.
The "TopGrade" column is:

=CALCULATE(MAX(Grades[Grade]),FILTER(Grades,Grades[Teacher]=Teachers[Teacher]))

The closest thing I've found it this but (obviously) I can't figure it out. Fill Table with Last Survey Result - Excelerator BI

Many Thanks,
Alex

 

[anvg]

If you sure that each teacher has one top student only then you can use a next measure

Top Students = SUMMARIZE(FILTER('Grades';'Grades'[Grade] = MAX('Grades'[Grade])); Grades[Student])

But if top students are more. In Power BI and Excel 2016 we can use CONCATENATEX

Top Students=CONCATENATEX(
    SUMMARIZE(FILTER('Grades';'Grades'[Grade] = MAX('Grades'[Grade])); Grades[Student]);
    'Grades'[Student]; ", "
)

But I do not know how to do that in Excel 2013.
Regards,