#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %HoH = (
    student1 => {
	quiz      => "result",
	exam      => "result",
	final     => "result",
    },
    student2 => {
	quiz      => "result",
	exam      => "result",
	final     => "result",
    },
    student3 => {
	quiz      => "result",
	exam      => "result",
	final     => "result",
    },
    );

print Dumper \%HoH;

__END__

$ perl test.pl
$VAR1 = {
          'student3' => {
                          'quiz' => 'result',
                          'final' => 'result',
                          'exam' => 'result'
                        },
          'student1' => {
                          'final' => 'result',
                          'quiz' => 'result',
                          'exam' => 'result'
                        },
          'student2' => {
                          'exam' => 'result',
                          'quiz' => 'result',
                          'final' => 'result'
                        }
        };