Every Sunday morning, Rod and Deonie Fiford would unfold a blanket, and a wave of Lego bricks would rattle across the table-tennis table in the rumpus room. The siblings would build cities, spaceships, helicopters and fantasy kingdoms. Rod would create the scenes, Deonie the storylines. For hours, they’d quietly click away with the blocks, hoping their parents would forget to take them to church.

Today, Rod is a mechanical engineer and university lecturer. “I couldn’t choose between architecture and engineering,” he says. “But playing with Lego that actually had motors and gears and things is what made me go, ‘Hey, this is cool.’” Deonie, a fiction editor, says playing as a child helped her explore narratives. “The way we played reflects what we’re interested in.”

Now 51, Rod has returned to playing with Lego – again, spurred by Deonie, 47, who a few years ago showed him one of their childhood Lego spaceships with some bits missing. While fixing it, he got hooked again and joined a team of like-minded Lego fans who create elaborate models for exhibitions. “You go through your dark ages,” Rod says of the years when he didn’t touch the building blocks. He laughs at being part of a market the toy industry calls “AFOLs” – Adult Fans of Lego. “I enjoy showing people at events that you can do something that looks reasonably realistic.”

We all have childhood memories of play: the discovery of nooks and crannies during a game of hide and seek, teddy bears as “best friends”, the water pistol your brother used to fire at your friends, the hula-hoop your sister seemed to spin forever, the Barbie whose hair you decided to cut one day, the deliciously squishy feel of Slime in your hands. And, yes, some of us might still find ourselves tinkering away at Lego or reliving childhood sports (via a games console), part of the modern wave of “kidults” travelling back in time through toys. But is there such a thing as a bad toy? And what makes a toy good?

First, what’s the point of play?

Primates and dogs chase each other, cats bat at objects, rats, mice and magpies play-fight. In fact, almost all mammals behave in ways that can be thought of as play. Exactly why has perplexed scientists for decades. Some have claimed play has evolutionary benefits – a way of building skills or bonding – while others believe there is little way of knowing what it’s for.

Working definitions tend to distinguish play as an activity for enjoyment rather than any productive or practical outcome. At the Strong National Museum of Play in Rochester, in the state of New York, chief curator Christopher Bensch says, “Play is really its own reward. That’s what makes it play. You may take up really valuable things along the way – the ability to collaborate with someone on a team or to play by the rules with a board game – but that’s not why we play. We play because we are choosing to, and it’s internally rewarding at some level.”

Play can take many forms, from make-believe to crossword puzzles to golf, even daydreaming, said developmental psychologist Brian Sutton-Smith. He begins his 1997 book The Ambiguity of Play by pointing out, “We all play occasionally, and we all know what playing feels like. But when it comes to making theoretical statements about what play is, we fall into silliness.” One of several ways that play is discussed in modern society, he contends, is through the rhetoric of “progress”: play as a form of social and cognitive growth for children, as much about development as enjoyment.

‘It starts ... when you sit in a sandbox and you try to negotiate, or argue with somebody, or just explore possibilities using words.’

Depriving children of the opportunity to play has been linked with developmental delays and physical and mental health conditions. The UN’s Convention on the Rights of the Child – Australia and 195 other states are parties – includes the right “to engage in play and recreational activities appropriate to the age of the child”. Ensuring children can play, educator Pasi Sahlberg tells us, helps them be “happier, healthier and more active, and if they go to school like that, they will learn more”.

Early childhood educators break play into types, including structured, with rules, or “free”, where children amuse themselves, such as primary schoolers at recess. “The kids can, basically, define and decide what to do, and how to do it, and how to play with whom, and often also create the rules for that,” says Sahlberg, co-author of the 2019 book Let the Children Play. To him, play is “the most natural way for children to learn about who they are and the world around them”. “It starts at the age of three or four when you sit in a sandbox and you try to negotiate, or argue with somebody, or just explore possibilities using words.”

Even the best-structured play lets a child follow their curiosity, says Kathy Hirsh-Pasek, one of the world’s leading play experts. She tells us from Philadelphia that young children tend to learn more words through singing, board games, or even through an app she created than simply absorbing by rote. “So when you can be purposeful but, at the same time, let the kid take the lead – then they really do quite a good job at learning.”

Play helps develop a child’s imagination too, which is a critical foundation for learning, says Marilyn Fleer, laureate professor in early childhood education and development at Monash University. “Most things that children learn, they have to imagine. So in science, for instance, the relations between the Earth, moon and the sun have to be imagined rather than experienced. Developing children’s imagination in play means you help children to better understand concepts that explain their world.”

Toys are the objects or props in play. “Imaginary play is when a child looks at a stick and imagines it to be something other than a stick … a hobbyhorse … a measurement tool,” Fleer says. They can enable children to play out roles and social rules they encounter in everyday life – the medical set, the fire truck. They’re a stimulus, encouraging children to explore their creativity or test themselves physically and mentally (pogo sticks, Rubik’s Cubes). And toys such as teddy bears can be soothing “transitional objects”, a term coined by British pediatrician D. W. Winnicott in the ’50s, providing an object of attachment as children go through a healthy phase of separation from their caregivers.

What makes a good toy?

Nola Firth was six in the 1950s when her mother gave her a toy koala made from kangaroo hair and stuffed with sawdust. Nola had dolls, toy cars and teddy bears, but the koala was her favourite. She named it “Blinky” after Dorothy Wall’s 1933 character Blinky Bill. “He took part in my imaginary life,” she says. “I did things like have funerals for butterflies and that kind of thing, and he would have been there. My main memory is that he was really sort of a companion. If things were difficult, he was there.”

Blinky, showing some wear and tear from its busy life with Nola, is today in the National Museum of Australia in Canberra. “We all know a kid like that, who is really attached to a squashy, cuddly friend,” says curator Laura Cook of the koala’s significance among the museum’s collection of more than 400 toys. There are bikes and balls, a 1920s dollhouse, colouring books and a set of coins that two children painted with a curious cast of royals and farmers during the Great Depression, as well as plastic Ned Kelly armour with a toy rifle.

Across the world, in the Strong National Museum of Play, you’ll find a Frisbee, a plastic disc that took its name from a local baking company whose plates or tin lids got tossed around in impromptu games of catch by college students in the late 1800s. There’s a range of yo-yos, too (the earliest known yo-yo appears on a vase painting from Greece that dates to about 440 BC). There are toys that imitate adulthood – Matchbox cars and a Fisher-Price farm set – as well as toys that are, essentially, building materials, such as Play-Doh and Lego (an abbreviation of two Danish words meaning “play well”). There are jigsaws, floor games (Twister) and board games (Monopoly) as well as sticks and cardboard boxes – choose your own adventure.

The top-selling toys in Australia in 2024 are from global manufacturers: Mattel’s Hot Wheels cars, the Barbie Dreamhouse, Lego sets, a Furby Interactive from Hasbro (the company that sold Mr Potato Head from 1952).

“In the post-World War II era, there was just a proliferation of kids and new suburban lifestyles with more leisure time and spending money for children,” Bensch says. “That dynamic has only magnified in the years since, and now we see unboxing videos on YouTube with influencers who are six years old who are creating kid-to-kid demand.”

Why do some toys endure for generations? “A good toy is one that gives a lot of room for kids to interpret and bring to it what they want,” says Christopher Bensch at the museum. Indeed, some of the earliest known toys are simple stone balls found in a child’s tomb from the Neolithic age near Xi’an in central China. Kathy Hirsh-Pasek puts it like this: “If what you’re looking at is going to be 10 per cent kid and 90 per cent toy, it’s probably not going to be fun. But if it’s 90 per cent kid and 10 per cent toy, that’s a great toy.”

Ask educators what they would put in a children’s toy box and they generally suggest a mix of manufactured toys and organic, or at least basic, materials. “Dolls, blocks, pieces of fabric, natural materials like sticks,” says Marilyn Fleer. For her own children, she made a sandbox in the backyard with toy tractors, trailers, figurines and cars. “And I have little slats of wood, so you can make paths that can be moved around. For slightly older children, I’d transform the toy box into a theatre, with props and favourite books to inspire their imagination.”

Is there such a thing as a bad toy?

The Strong National Museum of Play has dolls that urinate, a “harmless” dynamite model that uses an air pump to propel rocks as if exploding, and, astonishingly, a handmade miniature electric chair. “It’s about 20 inches tall, and we have never quite dared to put it out on display,” Bensch says.

Bad taste is one thing, but what about “one-trick” toys? Bensch points to the Tickle Me Elmo, a plush toy first sold in 1996 that shook with laughter when squeezed. A craze developed around it: stores sold out in the lead-up to Christmas that year, causing frantic shoppers to stampede in a Walmart in Canada and injure an employee, and the item to be resold online 50 times above its retail price. The toy “did one thing and that was giggle and wiggle and laugh”, Bensch says, “but he was doing it, you weren’t doing it”. (Newer versions make more sounds.)

Research is inconclusive on whether toys such as Nerf guns or shooting-based video games can lead to actual violence. Parents who prefer their children not to play with such games often have to navigate a child’s peers having them. “I didn’t want my kids to have toy guns, so I was, like, totally against toy guns. And one day, my oldest kid, he came in with a toy gun, and he made it out of Lego,” Kathy Hirsh-Pasek says. “Some you win, and some you lose.” Gender stereotyping is another vexed issue. “I think it’s really important to expose girls to blocks and boys to dolls,” says Hirsh-Pasek, although she adds: “For the four- or five-year-olds, that genderisation can happen no matter what. The girls just like tea time and dress-ups better, and the boys tend to like guns and building things.”

‘The odd thing is that, in many cases, the so-called educational toys aren’t really as educational as the toys that don’t brand themselves as educational.’

The notion of “educational” toys came with the rise of compulsory schooling in the 19th century. German educator Friedrich Froebel, founder of the kindergarten system, landed on six groups of shapes called “Froebel’s gifts”, designed to expose children to geometric shapes, which increase in complexity from a ball of yarn to a cube formed from dozens of small blocks. Twentieth-century architect Frank Lloyd Wright wrote that playing with the blocks as a child made him “susceptible to constructive patterns evolving in everything I saw”.

Many toys today are branded as educational, but experts have a hard time proving they can achieve narrow outcomes such as teaching children the alphabet. “The odd thing is that, in many cases, the so-called educational toys aren’t really as educational as the toys that don’t brand themselves as educational,” Hirsh-Pasek says. “If we control it too much, then no, that’s a curiosity killer.” She’s also researched shape-sorter toys with electric voices that congratulate a toddler when they correctly pair shapes. “They took over the parent-child interaction that would have otherwise happened. And there’s nothing more powerful for brain development than that early interaction.”

Then, of course, there’s time on screens: 40 per cent of children spend between 10 and 19 hours on screens a week outside of school, according to the Australian Bureau of Statistics (national screen-time guidelines suggest no more than two hours of recreational screen time a day). Meanwhile, since 2018, reading for pleasure has decreased by seven percentage points, and the demographic of children involved in creative activities is four percentage points smaller. Pasi Sahlberg says that except for a few computer games that require creativity to build, create or write, what children do on screens has “very little to do with play”. “It’s probably much more close to addictive behaviour rather than joy, curiosity and passion.”

‘Go with the kid’s vision. Let the kid tell you what he or she wants to do and fly with it.’

Licensed toys make up about a third of the toy market. Does a toy based on a movie franchise limit a child’s imagination? Marilyn Fleer says kids generally play by borrowing from storylines they know anyway, and laughs at one example where a science teacher gave children water and oil to experiment with, only for them to pull out a humpty-dumpty doll and use the liquids to medicate it after a fall. “Her view was that you provide the materials, and the children gravitate to science but, of course, they gravitated to a narrative that they knew.”

How adults play with children also counts. “The worst thing we can do as adults is take over by going, ‘Oh, you’re making a building, let me build it taller’,” Hirsh-Pasek say. “Go with the kid’s vision. Let the kid tell you what he or she wants to do and fly with it.” Today, Deonie Fiford builds with Lego alongside her daughter, Niamh, 9. “She’ll be making something, and I’ll be making something, and you can sort of talk about what you’re making,” Deonie says.

What does play do for adults?

When Pasi Sahlberg arrived at Richard Branson’s private island in the British Virgin Islands, he found an opulent pool and across it a tightrope. Sahlberg was one of a dozen experts and entrepreneurs at the tycoon’s retreat to discuss how education and play can get more out of people. They were asked to walk across in their clothes. Everyone fell in. Elsewhere, there was a zipline. Branson has commented before about the “spirit of fun” that can make a company fun to work for.

Sahlberg says this is more than just mucking around. “It’s like an invitation to go and do something different.” Having fun can help adults see situations in new ways, opening doors to innovation. “It’s a simple thing to do,” Sahlberg says of Branson’s pool. “But that’s the best environment where I’ve seen how to build something, design something, that is inviting people to ask questions and try this.”

‘It depends on how you define toys for adults: is that huge yacht a toy for a really wealthy adult?’

The toy museum in Rochester displays a Harley-Davidson in the lobby, with a question: Is this a toy? “Some days everybody has said yes, and some days everybody has said no,” Bensch says. “We are definitely better at collecting toys for kids than we are for collecting toys for adults. In part, that’s because it depends on how you define toys for adults: is that huge yacht a toy for a really wealthy adult? And we don’t have a dry dock here to put one in.”

Bensch says adults today have more permission to play than ever, whether online, through hobbies or, literally, with an object traditionally thought of as a toy. “Adults have, overall, more disposable income than kids do. So if you can get them inspired to build the Eiffel Tower out of Lego and can sell them a really expensive set – that is a good marketing tool.”

Fiford gets his first-year engineering students at the University of Sydney to play with Lego as an icebreaker and to test how comfortable they are just picking it up and making something. “It’s such a powerful toy to help just with creativity.” He can now afford to collect sets he couldn’t as a child. Lego manufactures roughly 15 per cent of its product in the States for adults.

In fact, “kidults” – consumers aged 12 or older – are the biggest growth area for the toy industry. “Increasingly, older teens and adults are purchasing toys as collectible items or for nostalgic reasons,” says Alice Sanderson, executive manager of the Australian Toy Association. “This growing category presents a significant opportunity for the toy industry, particularly as birth rates decline.” (In Australia, as in many other nations, birth rates are dropping.)

In Britain, one in three pounds spent on games and toys were adults buying for themselves, according to industry research group Circana. In the States, 43 per cent of adults bought a toy for themselves in the past year, including to collect. Big sellers include NFL football trading cards and Squishmallows, a line of plush toys created in 2017 by an American toy maker wanting to emulate the “kawaii” (cuteness) he’d seen in Japan. Meanwhile, vintage toys perennially fetch eye-watering amounts at auction. In August, a 1979 Boba Fett figurine (from Star Wars) that never made it to market due to its jetpack posing a choking hazard fetched just over $2 million, breaking a record for the most expensive toy ever sold.

“Most adults look at children’s play with toys with a kind of amazement at how they can be preoccupied so well with them, and they also look with amazement at the millions of ‘strange’ adults who still collect toys and presumably still fantasise about them,” wrote psychologist Brian Sutton-Smith. But, he ventured, perhaps both adults and kids are involved in fantasy play. “The difference is that while children have toys, adults usually have images, words, music and daydreams, which perform much the same function as toys. Our fantasies are the micro-worlds of inner life that all of us manipulate in our own way to come to terms with feelings, conflicts, realities and aspirations as they enter into our lives.”

Fiford’s own models have included vast pirate-ship scenes built with a small team over months. It’s all about attention to detail: water made of three layers of blocks with five shades of blue. Yet, while it’s the work of adults, making these scenes feels like play. “I’m playing with Lego, but I’m not moving things around as I did when I was a kid.” The most fun is when he displays a creation at an event: he likes to think it might inspire others to think of what they could make. “You create almost a snapshot of a playtime, frozen.”

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