Smashing Watermelons

A party game, usually in the Beach Episode of Japanese media, where someone is blindfolded, given a large stick (possibly a wooden sword), and directed to smash/crack a watermelon.

Similar to hitting a pinata in some western cultures, except without any goodies other than sandy watermelon.

One of the traditional summer beach activities in Japan, at least until environmental and economic concerns made it rather less popular.

Common variations:

Someone else (usually the Unlucky Everydude) is buried up to his neck in sand, and the watermelon is placed next to him.
The people guiding the blindfolded one intentionally direct him/her towards the Unlucky Everydude.
The watermelon smasher is a sword expert (Kid Samurai, Heir to the Dojo), and slices the watermelon perfectly.
The watermelon is destroyed by some other means, to the surprise and consternation of the other participants.

Not to be confused with the band The Smashing Pumpkins, or one of the staple bits of Gallagher's comedy act.

Examples of Smashing Watermelons include:

Anime and Manga

Azumanga Daioh: In the first Beach Episode, they don't have a stick and Tomo tries to split it with a karate chop. She never manages to hit it. The second time around, Tomo ignores that they have a bat, and Kagura takes the bat and splits the watermelon before Tomo can put everyone through the karate chop debacle again. Tomo whines about it for a bit afterwards, and Kagura tells her to grow up. In the manga's third one, they don't have a watermelon, and Tomo hunts desperately for something to smash.
Fruits Basket: Done at the beach, and Tohru talks about how she used to do it with her mom.
- And then when they actually try it, martial artist Haru smashes one with his bare hands, so Tohru decides to try it that way as well...
Full Metal Panic! Fumoffu: Sousuke's classmates try to set this up for him. He marches off some distance away, discards the wooden stick, and blows the watermelon away with a shotgun, hitting it dead on but Comically Missing the Point. As in, he not only complains that it's too simple, he also sprays Kaname with watermelon juice even though she chose her swimsuit specifically to show off to him. She's not amused.
- In the first FMP series Handsome Lech Kurz Weber starts hitting on Kaname at the beach whereupon Melissa Mao forcibly plants a watermelon on top of his head. Then Kyoko comes up and hits it with a stick.
Lucky Star: Konata mentions that only rich people would want to spend the money to do this, but rich people aren't usually the sort who would do it anyway. Sure enough, rich girl Miyuki's never done it. Konata also directly refers to the Fumoffu example above.
Mahoraba: Tamami ignores the shouted directions, walks right to the watermelon, and slices it neatly (using a wooden bokken) into quarters.
Nogizaka Haruka no Himitsu: While Yuuto and Haruka try to teach Shiina to swim at the school pool, the side characters suddenly turn up for no reason and act like they're at the beach. A watermelon is produced, Ninja Maid Hazuki is blindfolded and given a baseball bat, and she promptly breaks the bat trying to hit Yuuto.
- Later, a straight version of the trope is used during the actual Beach Episode.
Done several times in Ranma ½.
- Ranma was once forced to participate in a Martial Arts Watermelon Splitting contest, in which the participants must race to the finish line with their watermelon intact to win, while trying to break each others watermelons with a bokken.
- Tatewaki Kuno once turned this game into Training from Hell. He stood under a waterfall on the originally named Watermelon Island, and smashed every watermelon that fell off the waterfall towards him. A watermelon to the head gave him Easy Amnesia, but the training worked - whenever he saw a watermelon, his speed and strength would increase tenfold, allowing him to easily defeat his rival Ranma, who was unfortunately wearing a watermelon-print bathing suit. His new watermelon-slicing skills also made him a hit with ladies. Of course, Status Quo Is God, so when Kuno's memory returned at the end of the story arc, his newfound skill disappeared.
  - Actually, that's not true- he retained the skill, it's just that his training is subliminal conditioning to destroy watermelons. It's absolutely useless unless his opponent is holding or otherwise resembling a watermelon, something that Ranma is well aware of. In fact, Kuno himself knows that the Watermelon Island training is useless for combat- he never intended for it to be any use in combat (being so egotistic that he already considers himself unbeatable): he wanted to upgrade his talents at slicing watermelons in order to impress girls, particularly Ranma's girl-form.
In Urusei Yatsura there was actually a story where Lum, Ataru, Mendo and Shinobu tried to acquire a watermelon to play the game, only the town they were in refused to sell them due to their fear of the wrath of the local Watermelon God. The group wind up pissing off the Melon God anyway, and it turned out that it's terrible wrath was spitting watermelon seeds at the people who angered it.
Subverted in School Rumble because Mikoto almost drowned.
Done in Tengen Toppa Gurren Lagann, to show how utterly great Princess Classic Nia is at everything.
- Also played with somewhat: the dark stripes on the melon are actually an octopus-like creature's tentacles and it tries to dodge out of the way.
The To LOVE-Ru manga has the watermelon turning into a Naughty Tentacles monster. This is about par for the course.
Hidamari Sketch: No Beach Episode in this series. However, Yuno finds an inflatable watermelon-like beachball in the shed and plays around with it in this manner, "just to get the feeling."
In the Beach Episode of Bleach (episode 228), everyone fights a Naughty Tentacles monster, but it turns out that the monster is made of watermelon, and was part of a surprise watermelon smashing game.
Ichigo Mashimaro
In Sayonara, Zetsubou-sensei the watermelon says "Don't open it!"
Hanaukyo Maid Tai episode 9. Taro and the maids forget to play this during their Beach Episode, so they do it while most of the mansion's maids have gone home on vacation. Security chief Konoe does a #3 multiple times.
Done in the Beach Episode of Hoshizora e Kakaru Hashi. Ibuki repeatedly tries to smack Kazuma with the stick (leading him to accuse her of being able to see in spite of the blindfold), while Ui sniffs out the watermelon and hits it without needing guidance.

Live Action TV

Zoey 101.
Gallagher and his Sledge-O-Matic may be the first that comes to the mind of American audiences. Of course, he wouldn't be blindfolded and would smash anything that would make a big splatter.

Video Games

Fruit Ninja
Katamari Damacy: You can roll up a kid trying to smash a watermelon on the beach. You can also roll up the watermelon. The watermelon is twice the size of the kid.
Super Mario Sunshine. In episode 8 of Gelato Beach, you can smash giant watermelons for coins.
One of Sakura's power attacks in Pocket Fighter is to try this, with her opponent in the way.
In the PAL version of Ico, in your second play-through, there are watermelons growing at the edge of the beach at the very end. Ico can smash them by throwing them. And if he's carrying one of them when he walks over to Yorda to trigger the final cut scene, then the shot of her waking up is followed by a shot of Ico and Yorda, sitting on the beach together, eating watermelon.
In Persona 4, your team is relaxing at your home in August when Dojima brings home a watermelon. Several members of your team, as well as Nanako, express disappointment they can't smash it themselves.
A summer beach activity in Rune Factory: Frontier, where only you and a few girls participate.

Film

Iron Man 2. Tony Stark does this with his chest cannon as a party trick. His friends are not amused.
At the end of Mulan, Chien-Po actually uses a pair of watermelons for "breasts" to complete his disguise. He then takes the two watermelons out and smashes it against one of the Huns' faces.

Western Animation

Hey Arnold! Arnold's grandma smashs a watermelon to pieces to serve for dinner in one episode.

Real Life

The Melon Fest in Chinchilla, Australia, includes a number of melon-related games, including melon smashing. A regular fixture is an attempt by a local to smash as many melons as he can with his head in a minute (he holds the Guinness World Record in this regard).