The BBC's Liz George reports on the growing trend

Yo-yo sales are rocketing this year, with UK toy retailers estimating as many as 138,500 are being snapped up every week.

Sales go through the ceiling about once every 10 years, according to the British Association of Toy Retailers - not surprising for a product whose name means "to come back".

But as the 70-year-old craze takes hold once again, the toys have been banned from at least two schools after the headmasters branded them a safety hazard.

The head of Studley Green primary school in Trowbridge, Wiltshire, Steve Wigley, is telling pupils to leave their yo-yos at home.

Gleniffer High School in Paisley has taken a similar decision.

Looping the loop

Mr Wigley said: "I banned the yo-yos from school at the beginning of term after seeing some children doing what they call 'looping the loop'.

"They throw the yo-yo out and up over their head. I have nothing against the yo-yo personally, but when children are using them they are not particularly concerned about who is around them.

"Also, if you loosen the modern yo-yos they can slip and just spin at the bottom of the string. I was concerned in case they came apart because inside there is bolt which could cause problems.

"We haven't had any accidents at the school, but I have heard of people elsewhere being hurt.

"What I am saying is that they might be dangerous or they might not be dangerous but I don't want to take any chances."

Toy ban

Mr Wigley, who says he has not had any complaints from parents or children over the ban, said he has also banned pupils from bringing other toys to school.

He said: "We don't allow toys to school as a general rule because all it does is cause problems with children lending them and getting them back in two pieces.

"I also believe the yo-yos can be socially divisive because they can cost up to eight or nine pounds and some families might not be able to afford to buy them."