So what’s the problem with fidget spinners?One headteacher shared a letter from a Year 7 pupil complaining that lessons are being disrupted.“They are the latest craze and roughly seven people bring them into my lessons and share spares with other people,” the unnamed girl wrote to Chris Hildrew, head of Churchill Academy in Somerset. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. “So for us, this isn’t new at all. It just seems that the rest of the world has caught up. For autistic children in schools who are often segregated, thought of as ‘nerds’, in some ways it’s quite nice that it’s their thing that has become a must-have toy.” They are marketed as a stress-reliever to help children with learning difficulties concentrate in class.But fidget spinners have instead become such a classroom distraction that the handheld toys are being banned across schools in the UK.So what are fidget spinners?If you haven’t yet heard of the new craze sweeping playgrounds, a fidget spinner is a three-pronged, palm-sized piece of plastic or metal which spins around a central weighted disc – a modern version of the old spinning top.They can cost less than £2, but deluxe versions change hands for £40 and YouTube videos demonstrating how to do tricks with them attract millions of views. We have banned fidget spinners from lessons @ChurchillAcad – here’s why. So proud of our students! #pedagoofriday pic.twitter.com/3gIJoH4euv— Chris Hildrew (@chrishildrew) April 28, 2017 However, The National Autistic Society said there was anecdotal evidence from parents that the spinners are beneficial.Carol Povey, director of the society’s Centre for Autism, said: “Autistic children have a different way of experiencing the world around them. Many find it difficult to focus on what the teacher is saying – stuff going on in the background that other children can filter out, such as the noise of a projector or light coming in through the window, can be difficult.“Having something that spins or twists can help to ground and balance them. Many adults will carry something in their pocket that has the same effect. There is very little research about how these things work, but anecdotally we believe they do work. A number of teachers posted on the Mumsnet forum, complaining that the toys were ruining lessons.One said: “I’ve had two children bring them in today ‘because it helps them to concentrate’ – no, it helps them to annoy their peers and stops everybody else from concentrating [sic].“They are now in my desk drawer waiting for their parents to come and collect them.” I guess #fidgetspinners are all the rage. My daughter finally got one. You basically just spin it. I don’t understand. #kids pic.twitter.com/BRK2jdL4By— Amber Myers (@WhisperAmber) April 29, 2017 Do they have a practical use?Fidget spinners are marketed as tools for children with autism and ADHD. One primary school teacher told the BBC that they were included in the school’s budget: “Specialists coming into the school recommend them for children and we’ll buy them in for the children that are identified.”There is no supporting scientific evidence, and at least one expert has debunked the claims. Dr Mark Rapport, director of the Children’s Learning Clinic at the University of Central Florida, said: “Using a spinner-like gadget is more like to serve as a distraction than a benefit for individuals with ADHD.” It’s been 5 days, and the fidget spinner things are already banned in my school.— 🅱avid (@BronzeShow) April 29, 2017 @justintarte Fidget spinners are such a big fad that they have been a big distraction in my classroom.— Rich Siemons (@RichSiemons) April 23, 2017 “When you are trying to focus on your work, all you can hear is it spinning round and round. If someone around you has one you kind of get attracted to it because they are trying to do tricks and everyone else is looking at it. This means that I am not doing my hardest on my work so I get less done.“To sum up, I think they should be banned in lessons.”Mr Hildrew, posted a copy of the letter on Twitter and wrote: What are children doing with them?As the gadget spins it can be balanced on top of fingers, toes, or event the nose or forehead.More than one can be stacked on top of one another, creating a spinning tower that plays with your vision.As the forces come into play, the skill lies in trying to pull off various tricks and stunts. The biggest challenge is throwing a spinner to a friend and trying to catch it, a feat even more impressive to pull off than the successful bottle-flip.