IT IS the latest craze sweeping schoolyards across Australia, but it turns out the inventor isn’t making any money from it.

Catherine Hettinger knew her invention — the fidget spinner — was working as she sat alone before a meeting with the vice president of Hasbro, one of the largest toy manufacturers in the world.

“That was one good thing about this product: If I walked into their headquarters spinning it, it totally calmed me down,” Ms Hettinger told MONEY.

“It’s not an easy thing for most people to walk in and close big deals.”

It was 1997 and Hasbro didn’t see the magic in the low-tech toy, later sending a rejection letter to Ms Hettinger, whose patent for the first fidget spinner was approved earlier that year. Hasbro now sells the stress-relieving toys that are sweeping the country, as well as causing some trouble in classrooms.

The New York Post reports Ms Hettinger said she got the idea for the toy, which sells for about $5, when she saw young boys throwing rocks at police officers in Israel.

She wanted to find a way to distract young kids and give them something soothing to release pent-up energy.

“It started as a way of promoting peace, and then I went on to find something that was very calming,” she said.

Ms Hettinger, who began imagining the toy as early as the 1980s, initially considered a soft rock for kids to throw, but then developed the idea for the fidget spinner more than 20 years before they became the hottest toy this year and potential relief for some people who suffer from anxiety and attention deficit disorders.

But the craze came a little too late for Ms Hettinger, whose patent on the original product expired earlier this year. That means companies like Hasbro can sell their own versions of the toy without Ms Hettinger, who insists she’s not upset about missing out on the toy industry’s latest fad.

“Maybe if it was some kind of exploitative product — like a new style of cigarettes — and my only motivation was to make money, I’d have a different attitude,” she said. “But I am just thrilled.”

Children, college students and adults alike are scooping up the toys as a way to help them focus or release nervous energy. They come in a variety of colours and sizes and are markedly inexpensive — most versions can be bought for less than $5, although some made with copper or other metals can be pricier.

US chains like Walmart and Toys ‘R’ Us are reportedly having a hard time keeping them in stock, and a search of Amazon’s top 20 best-selling toys and games revealed that 17 were fidget spinners. (The other three toys were fidget cubes, a six-sided plastic toy with multiple stress-relieving activities.)

“When you start seeing these things flying off the shelf at your local 7-Eleven, you know things are heating up,” said Ms Hettinger, who isn’t sure what’s behind the sudden surge in interest in fidget spinners. She speculates it might have something to do with the recession of 2008, with people looking for cheap ways to have fun.

“That was always the concept — to help people,” she said. “I experienced it for myself … There’s a real need for this.”

Ms Hettinger, of Orlando, is now focusing on how to sell her original spinners and get them into the mix of the toys flying off the shelves. She’s launched a Kickstarter campaign with a goal of more than $23,000 and hopes to deliver her Classic Fidget Spinner as early as next month.

“Kids are required to sit seven solid hours in chairs and this is sparking a revolution to at least keep them from getting in trouble,” the website reads. “No animal sits still for long and we can’t either.”

Not everyone is a fan of the fidget spinner, however.

Some principals in Australia say the toy may actually be interfering with children’s learning.

This article originally appeared on the New York Post and was reproduced with permission