The ol' my dog ate my homework. Im serios, if you leave pages out my dog will rip it up and eat most of it, no one ever beleives me however.
The other was a weird one. I had a loose tooth, and I was pulling it out over my homework. So this tooth was a stubborn one, the ones that bleed alot. So I'm sitting there over my homework ripping my tooth out getting blood all over my homework. So I go into school with the page like half finished, my teacher asked why it was half finished and I told her (without showing her it). So she didnt beleive me, so to one of my classmates dismay I pulled out the sheet of homework, it had the bottom half practically soaked in blood, that one classmate threw up all over the guy infront of her.
That was a funny day, and I never had to make up that homework.