Move over bottle-flipping and homemade slime: Minnesota kids have a new obsession. Fidget spinners are the latest craze to hit classrooms, playgrounds and social media. But some schools say the spinning has gotten out of control.

The compact, colorful trinkets are made of plastic or metal and have a ball bearing in the middle, which helps spin the toy's outside weights.

The widely accessible spinners are marketed as an outlet for restless energy, but with so many students spinning, some school administrators are finding the fidgets to be more of a distraction than an aid.

"We found that early on they were a distraction to learning, because kids were pulling them out of their pockets," said John McDonald, assistant principal at Delano Elementary School.

"There is a use for them if they do have a need for them through an IEP, if a fidget helps them to concentrate," McDonald said. "Other than that we have banned them from school."

Fidget tools such as spinners, cubes and putty were originally intended as a one-handed tool to enhance concentration, reduce anxiety and stimulate learning, particularly in people with ADHD and autism who might have a hard time sitting still.

Now, kids across the country (and many adults) are using them as a toy, causing disruptions in school. Many teachers report that students are using class time to do tricks, such as balancing the spinners on pencils or twirling them on their noses.

Trevor Hins was first introduced to fidget spinners as a tool for his 5-year-old daughter, who has autism. Hins, of Farmington, said he hopes his daughter will be able to use a spinner as a technique to "manage some of her stimming."

Although Hins sees the benefit of fidget spinners for his daughter, they have proved to be distracting for his 7-year-old son, who attends an elementary school in Farmington where spinners have been banned, Hins said.

"He doesn't concentrate [on] other things better when using the spinner," Hins said. "He concentrates on the spinner. He [also] loses it or parts of it multiple times a day and then finding it consumes him."

A search for "fidget spinner" on Amazon yields 32,000 results with prices ranging from a few dollars to $460. Places like Walgreens and convenience stores can't keep them stocked. Many kids make their own spinners using parts from skateboard wheels or as projects in school using 3-D printers.

Joe Garritano has created a business out of the fidget spinner craze. His Wayzata-based Steampunk Spinners company has been "growing like crazy," he said.

Garritano's spinners range from $19 and up, and he gets custom requests from avid spinner collectors "who will pay anything."

"People want spinners with their names engraved, special shapes or rare metals," he said. "I work all night and weekend to keep up with production."

There are hundreds of videos on YouTube and Instagram from adults and kids showing their gadgets off and giving trick tutorials.

Some students have started online petitions asking their schools to lift the bans.