That day there was some Chinese Wrestling in the commons:
The entrance to the community garden and nursery.
These are the Whizzy Whirlers. And this is their Whizzy Whirling Court. I don't understand whizzy whirling (nor do I know its real name), but I do know it is the adult version of a extreme mega yo-yo. It's really big and requires a huge string and elaborate whirling arm movements. And the whizzy whirler makes a loud whirring sound like the drone of a landing space ship. You can hear it from far away such as when your walking on the sidewalk outside the park and when you mistakenly think this is the sound of an air raid.