Double-ball Knockout!
Equipment needed: 2 basketballs and a hoop.
This common practice game requires two basketballs and can accommodate any number of players. The object is to make a shot before the player in front of you makes his or hers, elimanating him or her from the game. No points are scored; the sole object is to be the last player standing.
Players line up single-file at either the free-throw or three-point line. The first two are each given a ball. The second player can shoot as soon as the player in front of them has released the ball. If a player shoots the ball and makes their shot before the person in front of them has been given a chance to shoot they are automatically out.
If a player misses their initial shot, that person can grab the rebound and try to put it back in. As long as he or she makes their follow-up before the player behind them puts theirs in the basket, they are still in the game. Because there are two balls in play, a common strategy is to aim to knock the other player's ball away from the goal and buy time to make a shot (hence the name). The person then has to retrieve their own ball and return to the court in attempt to make it before the person behind them. For this reason it's also called 'Bump'.
As soon as a player hits a shot, they pass it back to the next player waiting and move to the back of the line. The game proceeds this way until there is only one player left.
(Game rules copied from wikipedia.)