Here's the relevant snippet having errors:

my %Pages = (
    'Login'           => \&validateAccount,
    'Create Account'  => \&createAccount,
    'User Options'    => \&userOptions,
    'View Flashcards' => \&displayCards,
);

if ( !$q->param ) {
    loginPage();
}
elsif ($q->param('action')) {
    my $page = $q->param('action');
    $Pages{$page}->();
}
else  {
    noSuchPage();
}
[download]

When PerlJam sends an action parameter with the 'displayCards' value, he gets uninitialized value errors in the $Pages{$page} call.

My solution would be to say:

my $action = $query->param('action');
if (exists $Pages{$action}) {
    $Pages{$action}->();
} else {
    noSuchPage();
}
[download]

This would reveal that there's no key in %Pages named 'displayCards'. Instead, it's 'View Flashcards'. :)