#!/usr/bin/env perl -l

use strict;
use warnings;

use Data::Dumper;

my @classrooms;

my @students = (
    { studentName => 'John', studentSurname => 'Something',
        studentID => 9534, age => 12 },
    { studentName => 'Mary', studentSurname => 'Something2',
        studentID => 5489, age => 13 },
);

my %classroom = ( classroomID => 10, classroomName => 'classroom1' );

push @{$classroom{students}}, @students;

push @classrooms, \%classroom;

print 'Name of 1st student in 1st classroom: ',
        $classrooms[0]{students}[0]{studentName};
 
print 'The whole school:';
print Dumper \@classrooms;