The Toy Retailers Association unveiled the top 12 toys this Christmas, including L.O.L. Surprise! dolls, in London.Jack Taylor / Getty Images

Kids like weird things: Yellow sponge-boys, talking doe-eyed ponies, ruddy-cheeked rodents that say only “pika pika,” and, especially in the past few years, unboxing videos.

Kids’ unboxing videos are YouTube series in which children, or in some cases just disembodied hands, take toys out of their packaging and play with them as uplifting music plays in the background. One particularly popular video shows a small boy unwrapping and then assembling a child-size electric car, using plastic tools that would surely fall apart in less practiced hands. He then drives the car down the sidewalk through an eerily empty neighborhood to a playground that is also completely empty, where he plays by himself, presumably because all the other neighborhood children are busy watching YouTube. The video has 267 million views.

Toy makers, who are experts at capitalizing on children’s weird interests, have now figured out how to make a toy that replicates what kids like about unboxing videos. Enter the L.O.L. Surprise! doll, a sphere the size of a bocce ball that consists of seven layers of packaging. Kids peel away the layers of crinkly plastic, which contain stickers and messages and tiny accessories that are surely crunched under many a parental foot, and find a small, nearly naked plastic doll with giant Bette Davis eyes who measures just a few inches tall.

More than 800 million L.O.L. Surprise! toys have been sold since their debut in late 2016, and they were one of the top products sold on Cyber Monday this year, according to Adobe Digital Insights. This year, even more toy makers have caught on to the trend. Parents can now buy eggs, pods of foam, cake pops, burritos, and balls of many shapes and sizes containing mystery animals and figurines. (“Unrolling is the new unboxing,” said Ashley Mady, the head of brand development at the company that launched the burritos, called Cutetitos, in October.) Some balls contain “boy-themed” surprises, which include insects, octopuses, skateboards, ninjas, and a packet of a powdery substance, as well as my personal favorite, Poopeez, which are rolls of toilet paper that hold mystery capsules with names including Lil’ Squirt, Skid Mark, and Toot Fairy. (“These new blind capsules are creating a stink all over Kerplopolis faster than a fart disappears in the wind,” according to marketing material on Amazon.)

L.O.L. Surprise! dolls were created by MGA Entertainment, the company behind the oversexualized plastic Bratz Dolls that were a hit in the early 2000s. Isaac Larian, the CEO, told me in an email that L.O.L. dolls were essentially reverse engineered: The company wanted to cash in on the unboxing and collectibles trends, and so it came up with L.O.L. dolls. MGA Entertainment was told, at first, that kids needed to see a product before they would ask for it, Larian said. But L.O.L. dolls proved analysts wrong—kids can apparently want things without even knowing what they are. MGA Entertainment has since branched out into L.O.L. Surprise! pets, L.O.L. Surprise! houses, and larger L.O.L. Surprise! capsules, which contain dozens of dolls and accessories and retail for about 80 bucks.

At first glance, unboxing videos are an especially bizarre phenomenon to model a toy on. Kids are essentially watching other, luckier kids get lots of expensive toys, playing without having to bother with school, or nap time, or that perennial enemy, broccoli. Some unboxing stars have become millionaires—one 6-year-old named Ryan made $11 million last year, and all he really does is open toys, search for toys in his swimming pool, shop for toys at Walmart, meet life-size and slightly creepy versions of his favorite toys, and get along well with his parents. His YouTube channel has 17 million subscribers, and a video of him collecting giant eggs from his personal bouncy castle and then opening them to reveal toys inside has a mind-boggling 1.6 billion views.

There are biological reasons young children like watching unboxing videos, and it’s the same reason they’re drawn to surprise toys. Kids don’t really get good at understanding and anticipating the future until they’re about 4 or 5, Rachel Barr, the director of the Early Learning Project at Georgetown University, told me. At that age, they start looking forward to things that will happen down the road, and so they like watching videos that have an anticipation aspect to them. But kids of that age don’t particularly like being frightened, so they like videos in which they know that nothing bad is going to happen. Unboxing videos and surprise toys allow kids to enjoy the anticipation without being too afraid, Barr said, because they know roughly what will be in the package, just not the exact details.

Kids will watch unboxing videos over and over—or open surprise toys over and over—because they pick up new details every time, Barr said, figuring out how unwrapping works. Some of the most popular unboxing videos on YouTube are of surprise toys, including a 12-minute video with 321 million views in which a boy tears open a giant golden egg to find a load of Spider-Man-themed candy and toys, including a few smaller eggs that he also unwraps. The video, which is loaded with commercials, ends with him screaming in excitement as his final egg includes a little Spider-Man.

Unboxing videos have their benefits: They allow kids to connect with other people, experience toys that their parents might not be able to afford, and hang out, in a way, with other kids, even if they live in an area without a lot of children or where it’s too dangerous to go outside, according to David Craig, a professor at the USC Annenberg School for Communication and Journalism. Parents might not mind videos in which children watch other kids play with toys, he says, if it keeps them out of trouble.

Mary Lynn Hashim was confused when her 6-year-old started asking for L.O.L. Surprise! dolls last year, ahead of her December birthday. She ended up having to wait in line outside a Toys “R” Us in New York before it opened one morning to buy the toy, because it was sold out everywhere she’d looked and the store told her it was getting a new shipment. Hashim was standing next to her daughter, who is now nearly 8, as she talked to me, and asked her what was so cool about the surprise dolls. “You might get an ultra-rare,” her daughter said, referring to one of the less common dolls contained in the spheres. “Or the baby sister. It would be cool if I got the baby one.”

This desire for rare toys and dolls is what drives the collectibles industry, which itself is helping increase toy sales. According to the NPD Group, the global collectibles market grew by 14 percent in 2017, to $3.9 billion, led by L.O.L. Surprise! toys. That’s a victory for toy makers at a time when shops such as Toys “R” Us are closing their doors. But to some advocates, the fever over surprise toys shows how successful MGA Entertainment has been at marketing. They’ve convinced kids that toys are about collecting, not about play,  Susan Linn, a lecturer at Harvard Medical School and the author of Consuming Kids: The Hostile Takeover of Childhood, told me. “The problem with these dolls is the whole point of them is the acquisition,” she said. “It’s the notion that the things we buy will make us happy.”

When kids watched programming primarily on television, it was easier for them to know what was a TV show and what was a commercial. Now that they watch more content on YouTube, they might have more difficulty telling the difference. Unboxing videos are both a TV show and a commercial; they feature kids playing, but also kids shilling new toys that have sometimes been sent to them by the toy maker. Brands create whole TV series of kids playing with toys—the L.O.L. Surprise! channel has 758,000 subscribers and features two chipper girls who wear a lot of glitter and makeup and seem to have an endless capacity for excitement over small plastic dolls. In one video, the girls talk about how great it is to get a doll you already have, because then you have twins, or “BFFs,” or even a whole dance crew. Other consumers have made and uploaded their own L.O.L. Surprise! videos, which themselves have millions of views; some feature kids who are so young they can barely talk.

Jen DelVecchio’s kids, ages 10 and 4, don’t watch TV anymore. Instead, they watch videos on an iPad. But they keep coming back to unboxing videos and commercials on YouTube, which make them go crazy over L.O.L. Surprise! toys. She buys them for special occasions, she said, but then finds that the kids abandon them after opening them. “I think with my kids, the excitement is more unwrapping it than it is actually playing with it,” she said.

For Linn, this habit—of getting something and then immediately casting it aside for something new—is what is driving the popularity of surprise toys. Kids and adults alike have short attention spans, and are hungering for adrenaline hits to get them through the day. Kids receive those adrenaline hits by getting and opening new toys, and then casting them aside. “We are in basically an ADD culture, where we are all encouraged to move very quickly from one thing to another thing,” Linn told me.

Of course, not every kid who wants a surprise toy has watched an unboxing video. As often happens with kids’ obsessions, the weird thing one kid wants has become the weird thing every kid wants. Suzanne Barnecut’s 6-year-old daughter isn’t allowed to watch YouTube. But she still started asking Barnecut for L.O.L. Surprise! toys a few months ago, stopping by the toy aisle at Target to point them out. Barnecut bought a few of the toys for her daughter for Christmas, though she’s a bit worried about what will be inside, since there is no way for a parent to know ahead of time. “She definitely has not seen the videos, but all her friends have them, so they’re cool,” Barnecut said.

Surprises aren’t exactly new in the toy industry: Kids have long searched for prizes in the bottom of their Sugar Smacks or Cracker Jack boxes, and surprise toys aren’t all that different from the hundreds of toys that have cycled through kids’ playrooms and closets over the years. Kids desperately want some weird thing, nag their parents about it for days, and then get it, play with it, and cast it aside. But with surprise toys, they’re not nagging their parents about an actual toy that they want. They want the pleasure of consuming, to be let into the adult world of buying things, opening them, and then casting them aside.

Hashim, the mom who scoured the New York suburbs looking for an L.O.L. Surprise! doll, told me her daughter lost interest soon after opening it. She and her friends are now into a new toy, she told me. It’s a furry bracelet with an animal’s face on it that giggles and talks, and it’s featured in many an unboxing video on YouTube.

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