The first and second series of television show Round the Twist were written by Paul Jennings and based on his published short stories; episodes after this point were original stories written by other people. The lesser-known series Driven Crazy was likewise based on his previously unadapted stories.
His work is often quirky in style, often drawing upon weird, spooky and fantastical occurrences, including liberal amounts of gross-out humour and Nightmare Fuel. For these last reasons especially, Moral Guardians have frequently questioned the appropriateness of his work for younger readers. For much the same reasons, these younger readers have often loved it.
Jennings' work provides examples of:
- Ambiguous Gender: Star, the horse in Spaghetti Pig-Out.
- And, in earlier prints, Beethoven, the budgie in Only Gilt, and Ohda, the dog in Smelly Feat.
- Anyone Can Die
- Be Careful What You Wish For: His favourite Aesop.
- Big Brother Bully: The main character of Inside Out; the brothers of the main characters of The Velvet Throne and Ringing Wet.
- Body Horror: The main characters of Burp and Nails, amongst others. Clear As Mud uses it twice.
- Body to Jewel: The main character of Tonsil Eye 'Tis grows a third eye on his finger that cries tears that grow into garden gnomes. In the end, he starts a business selling them.
- Cloning Blues: The Copy.
- Ambiguous Clone Ending: Played With - The Copy has the same memories as the main character, and becomes convinced that he is the original, and that "The Copy" is trying to live his life. It soon turns out the story from after the boy uses the copy machine and passes out is told using the clone's memories instead of the original's, and the original boy is dead.
- Expendable Clone
- Downer Ending: Quite a lot.
- Hoist by His Own Petard:
"He screamed all the way down."
- In one story, the Jerkass narrator is a know-it-all bully who regularly taunts and teases people while scoring high on tests. Over the course of the story, the people who he taunts and teases receive free ice cream from a mysterious ice cream man, and subsequently lose the trait he was teasing them about (e.g. a pimply-faced character's acne disappears overnight). Infuriated that he doesn't get any ice cream, he breaks into the man's truck at night and puts sand in every tub but the one labeled "Smart Ice Cream - for smart alecks" which he helps himself to. The final part of the story is riddled with spelling and grammatical errors, as the narrator wonders what happened... and can't work out whether one plus one is "free or for?"
- Also, the Gizmos in the Gizmo series wouldn't have caused so much trouble if the characters had just left them alone in the first place.
- The main character of The Strap-Box Flyer sells a miracle glue that holds anything together... for four hours, at which point it falls apart. He never tells anyone of this limitation, leading to a trail of sorrows from the destruction of prized belongings to a child drowning. He runs into a man who invented the strap-box flyer, which lets you fly. As they fly towards the clouds, all sense of time lost, the inventor casually reveals the conman's flyer is held together with his glue, and just then it falls apart.
- In No Is Yes, Dr Scrape has isolated his daughter, Linda, and spoken in a way that has taught her all the wrong words to everything. When their house catches fire and he is trapped inside, a fireman asks her if anyone is in there. She replies "No", because she thinks that no means yes. Her father has literally killed himself because his daughter lacks the knowledge to communicate with others. It is suggested that she began to understand that she had been taught the wrong words and may have left her father to die on purpose, but from Linda's earlier behaviour, it is more likely she still thought "no" meant "yes".
- Hurricane of Puns: His joint books with Ted Greenwood and Terry Denton, Spooner Or Later and Freeze A Crowd.
- Jerkass: One will always show up in his stories, usually as an antagonist, rarely as a protagonist. In the Gizmo books, the protagonist typically does something wrong for the approval of this kind of character.
- Karmic Death: The abovementioned Villain Protagonist of The Strap-Box Flyer, whose lies lead to a death during the course of the story — a boy he sells his glue to drowns after his broken canoe falls apart again when the glue wears off while he's sailing it — and are implied to have caused similar deaths in the past.
- Magic A Is Magic A: His Twist Endings frequently follow logically from a previously established trait or truth of the work.
- Men Are Better Than Women: Played with in What A Woman. Sally is the only girl in her whole school and all the boys make fun of her because she comes last in all the Mini-Olympics events. Sally eventually proves them wrong when her athletic aunt's paperweight/trick box brings her good luck in both sports and other unrelated things. Eventually, the box is opened and all the boys faint to find her aunt's toe inside, while Sally doesn't. This is especially important since Sally's main tormentor has mentioned twice that only girls faint, so he proves that men are actually more faint-hearted than women.
- Mooning: The subject of Moonies.
- Naked People Are Funny: A lot of stories involve the characters being caught naked in public e.g. The Gizmo, Wunderpants and Pubic Hare.
- Only Mostly Dead: The main character of The Naked Ghost.
- Our Mermaids Are Different: In Nails, mermen and mermaids can crossbreed with humans, with said offspring looking human until puberty, when they will start to grow what look like extra fingernails (really fish scales) up their fingers and eventually over various parts of their body shortly before their legs fuse together to become the iconic tails.
- Picky People Eater: The Slobberers from the series Wicked!
- Scary Scarecrows: Know All features an scarecrow come to life when it wears an acrobat costume due to a circus curse. The protagonist recognizes that the costume belonged to someone bad, and the costume passes on the person's evil.
- Spoonerism: The whole point of Spooner Or Later.
- Tomato Surprise and Tomato in the Mirror: A number of his stories, but notably The Copy.
- Tongue on the Flagpole: The story Ice Maiden features a boy kissing an ice sculpture and getting stuck.
- Universal Remote Control: In the story "Spaghetti Pig-Out", a boy gets a remote that looks like a green chocolate bar that can control not only the VCR but people, flies, and cats.
- Urban Fantasy: Most of his stories.
- Verbal Tic: Without a Shirt is about a boy who can't help adding the titular phrase to everything he says.
- Widget: His stories can more or less be considered weird Australian things.
- Wipe That Smile Off Your Face: The last line of Santa Claws is, "I wish you didn't have such a big mouth."
- Fridge Logic: But the wish made before that should have wiped away all the wishes, and killed the granter.
- You Can't Fight Fate: Looking into the eye of a Seeshell lets you see the future, and everything you see will happen- however you can also manipulate Self-Fulfilling Prophecy.