Rules of the game of twenty-one

[Oz Referee]

OK. The way we used to play this when I was playing (and coaching) was that the coach would split the team into two lines, each one with the head at the "elbow" of the free throw line.

Each team would shoot a shot which would count 2 points if made. 1 Rebound could be put back, as long as it did not touch the ground. Rebounds counted 1 point, and successful shots could also be rebounded and put back (counting 3 points in total).

I don't know if this is the game you were refering to. But I hope that I have helped.