I grew up in Flatbush during the late 50s early 60s, and I played alot of skelley. What was really nice was that I hung out on a dead end street (E 22) and there wasn’t much traffic to interrupt the game.
I do recall a that there were usually a few games going at any given time, There was usualy a fresh board drawn to play on, although most of us took great pride in our ability to lay out “The best” Skelley court. The sale of chalk in my neighborhood was probably up there with milk or newspapers.

In my neghborhood, we only used soda or beer caps.
It was a blessing when twist-offs came out ’cause then you didn’t have to try and straighten out a bent cap to use it. Before them, opening a soda bottle, to get the cap became an artform.
We’d melt crayons into the caps, sometimes trying to mix and swirl the colors before it cooled.