Generating groups based on #of names and performance

Hello, I have a problem that seems far too complex for me to solve on my own v.v so help would be amazing. I am new to excel.

A sheet has the following column headers:

Student Score Rank Scores: High to Low Group

The student score is a percentage, the rank is calculated using the formula:

Formula:

=IFERROR(RANK(B2,$B$2:$B$36),"")

The values in the Scores: High to Low column are calculated using the following formula:

Formula:

={INDEX($A$2:$A$36,MATCH(1,INDEX(($B$2:$B$36=LARGE($B$2:$B$36,ROWS(E$1:E1)))*(COUNTIF(E$1:E1,$B$2:$B$36)=0),),0))}

There can be a maximum of 35 student names. What I would like to do is automatically generate groups based on student performance. Ideally there would always be 5 groups of students and any remainders would be placed into the group which contains the lowest performing students. So, if for example 26 student names are entered into the student names column, the group column might show “group 1” for the top 5 scoring students and “Group 2” for the next top 5 and so on. The last group of lowest performing students would contain 6. Attached is a sample spreadsheet.