The late dad of P shot this. When she posted it on FB, I recalled a similar pic by Cartier-Bresson.
Why do kids play with sticks and wheels? I never did that. Maybe the answer is in that awesome Slate piece: Why boys like sticks? Have to read it again.
And Wikipedia offers a large article on this called Hoop Rolling, a game as old as humankind. I missed it!
Henri Cartier-Bresson, Palermo, Sicily (1971)