(If you want to try it, install it via Google App Store)
Every time a new fad appears in the classroom, there are nay-Sayers saying how good/bad/whatever they are for children. Then they disappear, to be replaced quite quickly by something else - there usually seems to be a fad-free hiatus of anything from a couple of weeks to several months. Sometimes these fads, like these spinners, are related to things that have been around for ages, and can fulfill the same purpose, in this case the purpose fidget objects have for many people. But often kids have them simply because other kids have them. Then, of course, there are the adults who collect this sort of retro nostalgia stuff, with an attic stuffed full of Teenage Mutant Heroes cards, Moshi monsters, Star Wars memorabilia, and loom bands - but that's another story! Although they may be a fad for kids, fidget spinners for adults have been around for years. There is a fidget spinner database online that lists over 100 manufacturers. Many spinners are made of various solid metals (brass, stainless steel, titanium, and others) and cost many hundreds of dollars. Lots of different designs too. So, this isn't a fad!
But even if they were a fad, at least they wouldn't be as bad as bottle-flipping, which was the fad-du-jour late last year. How does bottle flipping work? Take any plastic drinks bottle, half fill it with water for weight, and then flip it vertically, with the aim being to have it land & stand on its base. The instability caused by the volume of water moving inside the container is what makes it a challenge. The downsides are that it's noisy (the water swishes in the bottle), it's visually distracting (flying water bottles aren't discreet), and as soon as one kid starts, every other kid in the classroom is digging in their bags to prove they can flip their own bottle better than the kid sitting next to them. Now, this is stupid!
When we were kids, for a while we used to go around with seriously powerful slingshots (with elastics made out of strips of car tire air tube) and we actually gave them up ourselves since they were seriously dangerous (as in: potentially deadly). Still, the pea shooters we mostly used in our local "wars" in the forest could potentially take an eye off if they hit directly (we used a kind of berry which was harder - and thus further flying - than peas). The point being that when pointed out to them, even kids will on their own do some level of risk reduction, just don't expect them to try go all the way to zero risk, since that almost always takes all the fun out of things. This was also stupid! Kids will be kids! Yes, someone will eventually be hurt. Unfortunately that goes for pretty much everything interesting in life:
- If you allow wrestling in the school gym eventually a kid will break their neck.
- If you allow kids to run in the playground eventually a kid will fall, crack their head badly and end up brain damaged;
- if you allow kids to climb trees eventually one will fall and break their spine;
- If you allow kids to play with toothpick and rubber bands eventually someone will lose an eye.
But the alternative is a childhood wrapped in cotton wool without climbing any trees or wrestling or running and that's a non-trivial price which gets paid by many many children for every one you save from some permanent injury or death. The rational way to approach the problem would be to quantify the risks in terms of QALYs (quality adjusted life years) or micromorts (each 1 in a million chance of death). A childhood that includes all these minor dangers has value it it's own right. It improves quality of life in a non-trivial way. But try selling that to the public : it's basically impossible to parade a million children who enjoyed their life a bit more than they would otherwise in front of the camera but easy to bring on the one poor kid with a shattered spine or a missing eye. I still fondly remember that I used to nick my granny's hairspray (those were the days) to make the best flamethrower in my neighborhood. Better than a magnifying glass for laying waste to small defenseless creatures; there was always some kid who said they knew someone who'd been killed when the flame backed up into the can and it exploded in his hand ("It's TRUE! I swear! I read about it. It happened in America."). Don't kids make their own dangerous 'toys' anymore? I also remember making a bow and arrow with a tree branch; lollipop sticks with a pin tied to one end with cotton and a small nut for weight and cardboard flight at the other end made a great dart; best was a sewing needle with a bit of wool threaded through and then fire it off blow-dart style with a narrow tube, pea-shooter or even a Bic Biro with the refill removed. Great at school firing one off and then hiding behind the desk lid.
Come September, the spinners will be forgotten by 90% of kids. At this time of year, shops have to be very careful with these things, because we're only a couple of months into the summer and they need to have enough in stock to milk the so-called fad, but not have too many left by the time the school start in September. Otherwise they will stuck with hundreds of spinners that no one will want any more, and they'll have to clear the shelf of all the left over loom bands to find somewhere to put them.
Not so with my version of the Spinner. It's here to stay. My little boy has been having a ball playing with it on his mother's smartphone. He keeps on asking for it in Manelês: "Pai, quéo spinna" ("Dad, I want spinner"; sorry, I cannot give a proper translation in English, but you get the gist)...
What do I need to go about it? Find a couple of equations regarding the angular momentum and the Force applied on the spinner. The rest is just code...Link on Google Play Store above if you care to try it.
r, radius of the object's circular motion
T, The cycle of the object's circular motion