This little doohickey is a Gee Haw Whammy Diddle. It's an old Appalachian folk toy from the mid 1800s that consists of a notched stick and another stick that you rub across it to make the propeller in the front spin. If you're good, you can make it spin. If you're lucky, you can make it spin the other direction. If you're a wizard, you can make it spin either direction on command. That's why it's called a Gee Haw Whammy Diddle. Old teamsters used to command oxen and other draft animals to go right or left with “Gee” and “Haw” commands. Apparently animals understand “Gee” and “Haw” better than “right” and “left”. If you know the trick, you can drive your friends nuts while you “command” the propeller to spin back and forth with your “Gee” and “Haw” commands.
Anyway, it's a fun little toy. Let me know if you figure out the trick. Or, if you prefer, you can just look it online too. Amazingly enough, there are actually Whammy Diddle competitions where you compete to see how many times you can reverse the direction in 12 seconds. Other competitions include doing it behind your back, doing it opposite-handed, etc.
On a personal level, my wife's Grandpa used to make these and sell them at craft fairs, along with his mason jar candy dispensers. Both were fun to recreate for a more modern manufacturing process.
Print some for the kids or grandkids for Christmas. It would make a great stocking stuffer (Santa definitely has and uses 3D printers in his workshop).
This does require a bit of assembly. You'll need a short (~`15-16mm) length of filament.
https://en.wikipedia.org/wiki/Gee-haw_whammy_diddle
https://www.ourstate.com/ramblin-man-whimmy-diddle-magic/
https://www.appalachianhistory.net/2017/12/all-i-want-for-christmas-is-whimmy.html