IT'S SMALL, round, and you pull its string. It can rock the baby, walk the dog - and causes controversy in playgrounds across the land.
The once-humble yo-yo is now a cult toy which even comes in a Pounds 100 titanium version, the SB2. More basic models are Pounds 2-Pounds 12.99.
The yo-yo's popularity is timely - in 1999 it will be 70 years since the toy appeared in Britain marketed by Frank Duncan and American millionaire William Randolph Hearst, the model for Citizen Kane.
But it is no poppet on a string, according to 260-pupil Studley Green primary in Wiltshire, where headteacher Steve Wigley says he is one of many heads who have chosen to ban it.
He said: "We do not allow toys because they cause fights. Children bring them in, their friends break them. That happens in the playground but the dispute is brought into class and the teacher has to spend time sorting it out before being able to teach."
A rather different approach was taken at 400-pupil Trelai primary in Cardiff where yo-yo enthusiasts from a local toy shop demonstrated moves such as walking the dog and rocking the baby.
Year 1 teacher Sarah Redman said: "It was a craze with all the children from the reception class to Year 6. When I was a child we played marbles and skipping. It just shows that every so often a craze comes in."
And in case you're wondering about regional variations, the Welsh for yo-yo is io-io.