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1.
Really overdue homework or homework that has been done but the teacher has either forgotten or chosen not to take it in.
Person 1: "Woah! I got this homework like 5 weeks ago and i haven't even started it yet!"
Person 2: "Dude, miss is gonna be mad, that's such mouldy homework."
Person 3: "No way man, you'll be fine, i've got so much homework in my folder and my teacher hasn't even taken it in yet. It's getting really mouldy."
by SAPCH November 03, 2010