Hehehe... very interesting. Below are my attempts -

Method 1 - Unnecessarily complicated

print qq{@{[qw/I will not throw paper airplanes in class./]}\n} for 1.
+.500;
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Method 2 - The C look alike

for ($i=0;$i<500;$i++) {
  printf("I will not throw paper airplanes in class.\n");
}
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Method 3 - Embedded text

my $line = <DATA>;
map { print $line } 1..500;
__DATA__
I will not throw paper airplanes in class.
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Method 4 - Simple obfuscation

$line="\n.ssalc ni senalpria repap worht ton lliw I";
print join'',reverse split//,$line for 1..500;
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Method 5 - Another obfuscation

%x=qw/airplanes 5 class. 7 I
0 in 6 not 2 paper 4 throw 3
will 1/; print qq{@{[map {$_
->[0]} sort{$a->[1]<=>$b->[1
]}map{[$_, $x{$_}]}keys %x]}
} for 1..length 'x' x 2 x 5
x 5 x 5 x 2; $a;$b;$c;$d;$e;
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Method 6 - Back to BASIC, my own embedded mini BASIC interpreter!

while(<DATA>){chomp,m/^(\d+)\s+(.*)/,$p[$1]=$2}{
  redo if ($p[++$pc] eq undef);
  if($p[$pc]=~/^(?:\s)*FOR\s+(\w+)(?:\s)*=(?:\s)*(\d+)(?:\s)*TO(?:\s)*
+(\d+)/x){
    $var{$1} = [$pc, $2, $3];
  }elsif ($p[$pc] =~ /^(?:\s)*PRINT\s+'(.*)'/x){
    print "$1\n";
  }elsif ($p[$pc] =~ /^(?:\s)*NEXT\s+(\w+)/x){
    die "variable $1 not defined!" if !$var{$1};
    $var{$1}->[1]++;
    $pc = $var{$1}->[0] if $var{$1}->[1] <= $var{$1}->[2];
  }elsif ($p[$pc] =~ /^(?:\s)*END/x){
    exit(0);
  }
  redo;
}

__DATA__
1   REM ****** BASIC PROGRAM *******
2   REM *** Print Text 500 times ***
3
10  FOR I = 1 TO 500
20  PRINT 'I will not throw paper airplanes in class.'
30  NEXT I
31
32  REM ****** I CAN DO NESTED LOOP TOO ******
33
40  FOR I = 1 TO 2
50    FOR J = 1 TO 5
60      FOR K = 1 TO 5
70        FOR L = 1 TO 10
80          PRINT 'I will not throw paper airplanes in class.'
90        NEXT L
100     NEXT K
110   NEXT J
120 NEXT I
130 END
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