Anvari's Law of Homework: A homework doesn't get created or destroyed,

Anvari's Law of Homework: A homework doesn't get created or destroyed,
but can be converted from one form to another.

Related:

• Just as there are laws of Conservation of Matter and Energy,
  so there are in fact Laws of Conservation of Pain and...
• MY HOMEWORK WAS NOT STOLEN BY A ONE-ARMED MAN MY HOMEWORK
  WAS NOT STOLEN BY A ONE-ARMED MAN MY HOMEWORK WAS NOT...
• It isn't homework unless it's due
  tomorrow...
• Von Neumann was the subject of many dotty professor stories.
  Von Neumann supposedly had the habit of simply writing...
• Mr. Bergstrom: Lisa, your homework is always so neat.
  How can I put this? Does your father help you with...
• Life can not be created or destroyed,
  it can only be screwed up...
• Homework time limit exceeded...
  Automatic logon commencing.....
• Since no matter can be created or destroyed (excluding nuclear and cafeteria substances),
  as one attempts to remove unwanted material (i. e....
• Mass-energy cannot be created or destroyed. It CAN,
  however, be wasted...