Fidget spinners are among the top 20 most-popular toys being sold on Amazon at the moment.
The fad is massive overseas and becoming popular in some New Zealand schools.
Students at St Thomas of Canterbury College in Christchurch are no exception.
"It's just a stress reliever pretty much," says student Harry Tellett.
But it could also end up with a line of boys outside the principal's office.
Some schools in New Zealand and overseas have banned them, saying the spinners distract the students from learning.
Opponents argue the toys are designed to entertain and are not an educational tool.
"If you're watching them spinning I don't know how you can be concentrating so I think they're more a distractor than something to stop children fidgeting really," says Canterbury Primary Principals Association's Margret Trotter.
St Thomas of Canterbury College is taking a more relaxed approach.
"If a kid comes to school and wants to work and they've got something spinning in their fingers, it's not really affecting anyone," says deputy principal Brendan Biggs.