At the time of the Teenage Mutant "Hero" Turtles (Psst, the BBC - we all called them Ninja Turtles anyway, you dicks), a variant of tag where instead of being it, you were 'Sexy Splinter'.

This is a photo of Splinter. Sexy Splinter. Phwoar. Splinter.
The most gay child in the class is Sexy Sue. It is Sexy Sue's task to run around, trying to grab the penises of the other boys. However, you can defend yourself by beating Sexy Sue to a pulp.
Game based around a tree.
One person would be elected the 'puller' and the rest of us would grab hold of the tree trunk for dear lives. The puller would attempt to remove pupils one by one from holding onto the tree by sheer force and if you were removed you then became a second puller and were then employed in removing others from the tree. The winner was the last one to be left clinging onto the tree.
This game, however, died a rapid death after some of the older boys said we all looked like we were trying to shag the tree. It did too.
The inability of English teachers to explain how Shakespeare or Chaucer could possibly be useful reading material is matched only by the pupils' inability to explain, in terms that English teachers accept, why it isn't. An impossible situation that will continue as long as there is oil in the earth.
From New Zealand. Mock any embarrassing situation with the word “shaaaaaaame”, following by a stroking of the chin between thumb and forefinger.
Regional variations; “Shamola!”, where you rub the forefingers of either hand together, and oddly enough, in Wellington, of saying “TAAAAAAAAY!” and pulling a lower eyelid down.
(Shame in England can be accompanied by licking the finger and holding it to the shamed person's face. The heat of their embarrassment will cause the spit to "sizzle". Well, it won't, of course - that's why you have to shout "sizzle".

Lunchtime entertainment based as loosely as possible on the classic 80s arcade game Arkanoid.
Arkanoid was a posh version of Breakout, and involved moving a bat around to bounce a ball against some blocks.
Arkanoid didn't involve our class headcase chasing us around school trying to whack us around our shorts-trousered legs with a large ruler. This was known, unlike the game Arkanoid, which this doesn't resemble at all, as "crisping".
You were briefly immune from crisping when you stood on a desk. Arkanoid had no such safety zone. However, to maintain this safety, you had to jump from desk to desk, like in Donkey Kong. Not Arkanoid.
Pre-Feargal solo, but possibly not pre-Undertones. On Charity No-Tie day - freedom of expression for 50p - anyone not undoing their top shirt button was said to be Sharky. I do not know to this day whether this was an insult or not.
Original played by screwing up a piece of paper in Mr. Sharpe's lesson and throwing it around until he noticed. Later , in the abscence of Mr. Sharpe's class, drawing pins were pushed through the paper before it was launched, causing some pain to the catcher. The lengths we went to, just so that we could play Sharpe Ball without the name seeming inapt.
Someone getting a brand new Helix plastic ruler was generally acknowledged as the opening gambit of a game of Shat Poo. Similar to Speednob, the brand new ruler would carefully be passed to owner of the sharpest compass, who would then scratch away the crazily jagged 'Shatter Proof' logo until only 'Shat Poo' remained. The modified ruler would then be replaced carefully into the victim's pencil case and hilarity would ensue (as it so often does) on discovery.
A variant of the game shat poo for owners of new Shatterproof rulers who were suspected of being gay.
Well - you had to be sure.
Before repetition lent the cliché some meaning, I thought the advert for Dempsey and Makepeace, which contained the line "she's as cool as a cucumber" was surrealist nonsense. Thinking I'd learned a new funny phrase, I took it into my active vocabulary without question. So when I nodded intelligently in primary school and noted that Miss Kaveska was as cool as a cucumber, thinking it was a joke, I must have sounded a right little turd. Ah well.
Descriptive of eyes after smoking first, illicit marijuana cigarette. No, your mum won't be fooled by you sucking a polo and spraying your jumper with Lynx.
This commendable practice began innocently enough when Carlos Dunbar claimed he had snorted three tubes of Sherbert Dip resulting in an "amazing" high. Soon most of the class were snorting incredibly fat lines of sherbert directly off German texbooks in class. The procedure would usually be to pour, chop, snort and then bellow as loud as possible to indicate the strength and status of your "high". With a particulary fat line, sherbert-activated mucus foam would pour from your nose, covering yourself and those near you. Soon we were making "wraps" of sherbert and I had cunningly placed my "gear" in an old Tic-Tac box, making a rather dapper "snuff box", which was quite a hit with the laydez. As anyone who's seen Scarface or Pulp Fiction will know, this halcyon period could not last forever. Our Jimi Hendrix was Andrew "Tarby" Tarbet. On running out of Sherbert during one especialy fraught German lesson Tarby, driven mad with need, crushed up a packet of Refreshers in the hope of a "hit". After snorting most of a packet of crushed up refreshers a woozy quiet descended over Tarby. Suddenly blood began to gush from his nose onto his books, trousers and Louisa Milne who sat in front. Soon bits started coming out with the blood and Tarby fled to the toilet, presumably to die. After this shock, nasal Sherbert consumption tailed off and was almost completely over within six months.
Upon making a mistake it is customary to acknowledge this to your friends by wrapping your upper lip round your top teeth, pressing your index finger on said lip and saying 'Sheudy Meu'.
Shinny the shoe was probably a nice kid but was never going to fit in because he had a briefcase, and even more unforgivably, shiny shoes. Word quickly spread that it was good luck to touch Shinny's briefcase and his shoes at the same time - but you must never speak to him during the act, as this would immediately undo the good fortune.

Shinny led a distraught and solitary life, and the nickname accompanied him into his early career. I like to think his personal accessory choices may have helped him along a bit in the real world of work, as some kind of compensation.
An offshoot of graffiti art, thought to originate in schools around Leicester. Often using twigs or lollipop sticks, urban artists would find fresh dog shit and thrust the sticks into the poo. What remained was both a work of art, and an Excalibur-style weapon, for a brave child to withdraw and wave around threateningly. Such a brave child had to be very careful of the "double dipper"
The first incidence of shit writing in my experience was someone writing shit, in shit, on the toilet wall.
"What's that?" someone could ask.
"Shit," their friend might have replied.
"I can read, thanks, I meant what is... oh."
A week later the words "GUNS 'N' ROSES" appeared on the same wall. Not spelled out in Guns and Roses, though. Still shit.
A game loosely based on "Street Hawk", TV's motorbike Knight Rider. The rules; after school, Steve Wild's little brother would ride around the playground on his BMX as close to 200mph as he could get, while we threw rocks at his wheels.
It ended, as all good things must, when Steve launched a set of those elasticated hooks used for securing luggage to roof racks into the front wheel at close range. His brother flew headlong onto the playground. I'm not sure how badly he was hurt because I did the honorable thing and legged it.
The computer room had monitors and BBC B's all the way round the outside. If you got in quickly enough after break it was your job to switch all the monitors on to save time.
However, if you were second in, it became your role to go round all the monitors and 'wipe' the static off - storing it up for discharge into the neck of the biggest girly mong you could find.
Turn a normal cookery lesson into shoe cookery by putting a rival chef's shoe into a pre-heated oven.
For dessert, pour ribena in the CO2 extinguisher's horn and spray it all over the ceiling.
An amiable enough game where you stand right in front of your opponent and take it in turns to see who can spit closest to the other person's shoes without actually hitting. If you did hit the shoe or trouser, they are allowed to spit on you anywhere. It's only polite, really.
It all began when someone tried to kick a football and their shoe came off. From there, it was natural progression to see who could flick their shoe the furthest, and then why not start a fight with shoes?
It all ended when a shoe went through a window and the culprit was immediately identified as the kid with only one shoe on.
The unexpectedly inventive nickname for polyester wadding which was one of the two major materials we used for making everything in first year Textiles. The other was paper.
First invented by Darren Kitching it caught on quickly to the point where everyone was chanting it constantly during Textiles. Unfortunately for me, the teacher had outlawed the practise while I was in the toilet and so finding the class strangely quiet on my return I started the cry once more. This got me 2000 lines that were to read "Polyester Wadding is not a popular music group".
A little excessive, I feel.
The windows in some of our classrooms would often steam up with condensation during lessons.
We discovered that if you had greasy skin (as many teenagers do), you could rub your fingers on your face, transferring some 'facial grease' onto them and then write 'invisible' words on the glass when dry, e.g "Bill Marlow is a Cunt".
When the windows next steamed up (which could be during another class) the invisible words would miraculously 'appear'. Often the blame would be directed at innocent pupils and once a whole class got detention for not revealing who had done it; they really didn't know! IT WAS ME! HA!