Some time ago (in the 1990s, I think) a women who had relatives with autism designed a toy thing that provided some sensory "stimming" activity.

The toy market is brutal. She wasn't wealthy and couldn't afford patent stuff; she didn't manage to make much (if any) profit, so she dropped the patent in 2005.

The toys are a set of 4 bearings held in a plastic frame. http://www.asseenontvandbeyond.com/assets/images/fidget-spin...

You can get deluxe versions using metal frames and ceramic bearings, and some spinners use two bearings not 4.

You pinch a bearing between two fingers and spin the frame.

The toys have a legitimate use for people with autism. It's a shame that they're being misused in classrooms.

https://news.ycombinator.com/item?id=14271914