I still remember one time I was marking a 1st yr uni Calculus assignment. Found this kid made a really "creative" mistake in a problem that amused me greatly. Then I marked the next assignment... same "creative" mistake! I marked another one and could see a pattern...

Apparently these 3-4 kids were identical not just on this one problem, but the whole assignment word for word!
What upset me most was not the fact that they copied each other... but the fact that they were too dumb to even "cheat properly"...
Moral of this story I told my class afterwards:
(1) After you copy from your mates, DO NOT submit your assignments together, one after another. It'd be a lot less noticeable.
(2) If you have to copy, then copy from someone who's ACTUALLY smart.
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