A Dog Ate My Homework

Basically, this is any child character explaining to his teacher why he hasn't done his homework. This will be either a lie, which may or may not be believed, or a Cassandra Truth. If it is the latter, expect them to also bring in the evidence proving their case (such as moist bits from homework, or even the animal itself.) The most common variant involves a dog, but other animals can be used as well.

Though this has become a Dead Horse Trope, and children rarely use this excuse seriously, the second variation on this trope is in fact Truth in Television. Many dogs do have a thing for paper, or are just Extreme Omnivores.

Anime and Manga

 * In Futakoi, Nozomu is always wary whenever the goat is around when he's doing his homework. No one believes Nozomu because the little bastard is nice to everyone except him.

Comic Books

 * A Disney Adventures Goof Troop comic had PJ offering this excuse for his homework. Though he had the sense to bring Chainsaw, still attached to said homework, with him.

Fanfic

 * "Hey Scot yuo must do are homeork an yurs but well eat yurs so you get a bad grad LOL!" My [mad dog] bros sayd an started to pump at me.
 * Someone from Harry's year in Oh God Not Again had to turn in their homework in tattered ruins, after the book Hagrid asigned for his class tried to eat it.

Literature
"Sally: I might have a little trouble reading it. *shakes Snoopy* I SAID...I might have a little trouble reading it!"
 * Aliens Ate My Homework (they really did, too). It doesn't end well, but the aliens appreciate how the apparent Refuge in Audacity helped cover for the other weird things that were happening.
 * Discworld:
 * Mentioned in Thief of Time, in that no dog dares to eat homework given to Susan's students. Instead, they sniff it out and carefully bring it to her class if the kid forgot. She is like that.
 * In another Discworld book it's mentioned that at Unseen University, your homework could eat the dog.
 * A Peanuts picture book has a literal version. Snoopy was playing WW 1 Flying Ace and pretended Sally's book report was sensitive papers. She chased him and he swallowed the report. So she takes him to school the next day and takes him up in front of the class.

Live Action TV

 * In one season 10 episode of M*A*S*H, Hawkeye gets in serious trouble because a goat ate the entire payroll (and, naturally, no one believes him; he is charged with stealing it). Later, Hawkeye is finally proven innocent when the goat subsequently eats a general's report on the issue. Seems sort of the same thing in spirit.
 * Briefly mentioned in an episode of Wizards of Waverly Place when the Russos adopt a dragon that's been transformed into a beagle. At one point, the dragon dog sets Alex's homework on fire, to which she comments: "The dog burned my homework, that's a new one."
 * In the Star Trek Deep Space Nine episode "The Nagus", Nog tries to explain why he hasn't done his homework. The only excuse he comes up with is that "Vulcans stole his homework".
 * Ren Stevens in Even Stevens, when having to be paired up with a Pig, ended up having her homework eaten by the pig. She tries to explain this to her teacher, with predictable results.
 * An episode of Ned's Declassified School Survival Guide involved Ned giving tips on good excuses. He comments that saying a dog ate your homework is a bad excuse... right before a dog eats his homework. The rest of the episode has him trying to find the dog and convince his teacher Mr. Sweeney that he wasn't lying.
 * Married With Children invoked this trope in an episode where Peggy goes Back to School because she didn't pass home economics (no surprises there). At a scene, a teacher asks the class to wake Kelly, who quickly responded that her dog at her homework. Later on, when Peggy is introduced to class, both her and Kelly fall asleep and the teacher asks the class to wake them both, who responded that the dog ate their homework.
 * In one episode of Tattooed Teenage Alien Fighters From Beverly Hills, one of the heroes was doing her homework when they've been called into battle. She then took the homework with her, eventually leading to the homework being eaten by the monster. The teacher later sarcastically asked if a dog ate her homework. She answered it was a monster and the teacher took it for sarcasm.
 * Superhuman Samurai Syber Squad had an episode titled "A Virus Ate My Homework". Unlike what the title might have made fans expect, Sam's homework wasn't eaten. His little sister painted it over. Fortunately, the emergency caused by the virus made the students go home earlier, allowing Sam another day to redo the homework.
 * Invoked in the lyrics to the theme song for Saved By the Bell.

Newspaper Comics
"Rerun: We don't have homework in kindergarten.
 * Calvin and Hobbes provides the page image.
 * The Far Side: One cartoon has a class full of dogs with the teacher asking, "Well, here we go again... Did anyone here not eat his or her homework on the way to school?"
 * On FoxTrot, Jason's iguana has eaten his homework. In some cases, Jason's iguana also ate his siblings homework, causing them to either force Jason to fix up their homework (and it is also implied in the final panel that they were actually feeding the iguana their homework), or tell Jason off for feeding the iguana the wrong homework assignment.
 * A 1995 Peanuts strip has this variation:

Lucy: I know. You're lucky.

Rerun: When we do, I'll tell the teacher my dog ate my homework.

Lucy: You don't have a dog.

Rerun: I'll borrow a dog.

Snoopy: Write your homework on a doughnut, and I'll eat it."

"Kid: A dog made me eat it."
 * In Dilbert, a kid tries to invoke this with Dogbert. It ends badly.

"Jon: What are you doing at the class reunion?
 * Garfield:
 * In this strip Garfield passes by a dog, who holds a sign saying: "Will eat homework for food".
 * In another strip, Jon goes to a class reunion, and meets his old English teacher, Mrs. Fronzak:

Mrs. Fronzak: Waiting on that overdue term paper, Jonny.

Jon: My, huh, cat ate it!

Garfield: Leave me out of this!"


 * Garfield also finds out that this is actually a very lucrative business for dogs.

Web Comics

 * Sandra and Woo:
 * In one strip, one of the other girls in class, on being asked about her homework, admits that she ate it herself. Specifically, Larisa put it through a blender and force-fed her the resulting mash. Nobody believes it, of course, but Sandra notices an electrical plug poking out of Larisa's backpack... and considering Larisa's nature, you really can't put it past her.
 * Larisa also once tries the excuse that her father ate her homework.
 * Florence of Freefall was asked in one strip if her owner ever asked her to eat his homework. She replies "Of course not, it was all done on the computer. He taught me to delete it instead."
 * Gil from Girl Genius once said in fever "Sorry, professor, my latest experiment ate my lecture notes..."
 * In one Kevin and Kell strip, Rudy claims "I accidentally ate my own homework".

Western Animation
""You ate my homework? I didn't know dogs really did that.""
 * An episode of Angela Anaconda had Angela's dog actually eat her homework, but of course no one believed her.
 * Kick Buttowski: Kick tells his teacher, "A dog ate my homework," and it's the truth. A vicious little dog did (and is shown in Flash Back) eat his homework.
 * The Simpsons:
 * In one episode the dog really did eat Bart's homework just before he left for school. Naturally, his teacher didn't believe him.

"Kronk: Come on, "A llama ate my homework"? It's the oldest excuse on the book.
 * When the family dog, Santa's Little Helper, starts working for the police, Bart has no choice but to eat his own homework.
 * In an episode where Bart's teacher starts dating Ned Flanders and saw Santa's Little Helper, she asked Bart if that's the dog that eats his homework. Trying to convince her by giving the dog a homework for him to eat. The dog refuses. Bart then covers the homework with dog food. The dog ate the food, cleaned the paper and signaled the answer of a math question.
 * In Codename Kids Next Door, Numbuh Five has a genuine problem of her homework getting eaten every day by a dog she passes by on the way to school. She has enough and decides to take the problem head on. Turns out that . And, even then, it's only because This turns out to be useful for the KND because
 * The Secret Files of the Spy Dogs had Sheela's dog eating her homework... on purpose. Because she has accidentally created a formula that seizes the king-side doggie food packs, Von Rubie tries to rewrite the homework from scratch, but when his mistress arrives... Needless to say, the trope happens, as well as Rubie escaping through the window.
 * One short in What a Cartoon Show has a cowboy telling his teacher his dog ate his homework. Obviously she doesn't believe him, but he tries to prove it by pulling out a dog chewing on a piece of loose-leaf paper. The teacher responds by lecturing him on bringing pets to class.
 * The Emperors New School has a variant where Yzma plans on forcing Kuzco to give this excuse.

Yzma: Exactly! It's so old, no one will believe him."

"Teacher: Bad dog! Gimme that!
 * An episode of Cat Dog was entirely devoted to the citizens of Nearburg making Dog eat their homework, which Cat exploits for their money. However, when the big one comes where Dog must eat the Mayor's written speech before he speaks up front, he becomes sick from eating too much homework, and Cat is forced to eat it himself. This turns out to be a bad decision as the entire crowd finds the idea of a cat eating homework ludicrous and boo the Mayor off the stage (and into the clowning business).
 * In one episode of Arthur, the Brain deliberately flouts several superstitions to show there is nothing in them, then has a terrible streak of bad luck, including having a dog eat his homework, which causes him extra distress because he knows how the report will be received.
 * In Animaniacs, this is a joke waiting to happen when the Warners attend school. Even when it was their first day. Turned out the dog was Wakko.

Wakko: Grrrr..."


 * In Recess, TJ managed to have his teacher believe this showing his homework shredded and drooled (which was done by him and never started the assignment). She didn't believe it since he still had a scrap of paper on his lip.
 * In The Amazing World of Gumball, Darwin and Gumball said their dad ate their homework. Naturally, no one believes them, and naturally they were right ("I thought it would make me smart!")
 * In Tales From the Crypt Keeper, there was a boy who, instead of using a dog, used a monster as an excuse. He told a homework-eating monster another monster showed up before. After a trip to monster land, the boy confessed and the monster took him home and made him do two homeworks: one to be eaten and another one to be taken to school.