Perl - 152 bytes

$h="-hundreds were a time for";say"The eighteen$h rum.\nThe nineteen$h fun.\nThe two-thousands are a time to run\na civilized classroom.\n"x(length$h);

This makes use of perl's string repetition operator and exploits a substring of length 25.

Ungolfed version:

$h="-hundreds were a time for";
say "The eighteen$h rum.\nThe nineteen$h fun.\nThe two-thousands are a time to run\na civilized classroom.\n" x (length $h);

Perl - 152 146 bytes

$_="-hundreds were a time for";say"The eighteen$_ rum.\nThe nineteen$_ fun.\nThe two-thousands are a time to run\na civilized classroom.\n"x y///c

This makes use of perl's string repetition operator and exploits a substring of length 25.

Ungolfed version:

$_ = "-hundreds were a time for";
say "The eighteen$_ rum.\nThe nineteen$_ fun.\nThe two-thousands are a time to run\na civilized classroom.\n"x y///c

Perl - 152 bytes

$h="-hundreds were a time for";say"The eighteen$h rum.\nThe nineteen$h fun.\nThe two-thousands are a time to run\na civilized classroom.\n"x(length$h);

This makes use of perl's string repetition operator and exploits a substring of length 25.

Perl - 152 bytes

$h="-hundreds were a time for";say"The eighteen$h rum.\nThe nineteen$h fun.\nThe two-thousands are a time to run\na civilized classroom.\n"x(length$h);

This makes use of perl's string repetition operator and exploits a substring of length 25.

Ungolfed version:

$h="-hundreds were a time for";
say "The eighteen$h rum.\nThe nineteen$h fun.\nThe two-thousands are a time to run\na civilized classroom.\n" x (length $h);