First there was bottle flipping. Now there's fidget spinning. Fidget spinners are the latest toy craze sweeping through schools across the country. Some say they can be useful for kids who have a hard time sitting still, but many schools say the toys are just too distracting in the classroom.

Fidget spinners are small toys typically made of plastic or metal that contain ball bearings that help the toy spin. They range in price from a dollar to several hundred bucks and can be found everywhere from Walmart to Amazon to 7-Eleven. They are flying off of store shelves faster than store owners can stock them.

If, like me, you were clueless about what a fidget spinner is or does, here's a little primer:

As their name implies, fidget spinners are marketed as gadgets that can help both kids and adults who have a hard time sitting still. Studies have shown that children with attention deficit hyperactivity disorder (ADHD) concentrate better in school when they are allowed to fidget. The idea is that by giving kids something to keep their hands busy in the classroom, they will be able to focus more on their schoolwork.

Stress balls, silly putty and exercise balls have been incorporated into many classrooms to help students who need these types of tools. But parents of kids with ADHD and similar conditions say that unlike these other tools, fidget spinners are cool and help their kids fit in while relieving anxiety and stress.

Distracting by nature

I can easily see why these things might become annoying in the classroom. What I can't see is how they might actually help a kid release anxiety and tension via fidgeting. There's little movement on the human end. It seems like the object is to spin it once and then let the toy do all of the moving to keep it spinning. And unlike stress balls or other tools designed to help kids with autism or ADHD concentrate, the object of the fidget spinner is to watch it spin. And that's distracting.

"He doesn't concentrate [on] other things better when using the spinner," said Trevor Hines, dad to a 5-year-old daughter with autism and a 7-year-old son who's not on the spectrum. Hines told the Star Tribune that he does feel like his daughter receives some benefit from using the spinner, but not his son. "He concentrates on the spinner. He [also] loses it or parts of it multiple times a day and then finding it consumes him."

How long will the fidget spinner craze last? For some teachers, it can't end soon enough.