The game of 21 is actually a version of 1-on-1, and helps you hone your basketball skills. You need at least one other player to play, and it's easiest to play at a playground with a marked half-court. All players play as individuals. The game begins with Player No. 1 dribbling the ball from the three-point line and trying to make a basket. If she misses, she can go for the rebound and shoot again. The others play defense, trying to prevent her from getting a basket. If she sinks it, Player No. 1 gets a point and the next player takes the ball out from the three-point line. The first player to get 21 points wins [source: Lifetime].
Scoring rules vary in 21. Some count a basket as one point, while others count it as two. You may give shots made from the three-point line three points or not -- it's your decision. A player can win by hitting 21, or may have to hit 21 plus be ahead of the next player by at least two points [source: Games ... For All Reasons!]. Typically, standard basketball rules apply. So double dribbling isn't allowed, and a foul is still a foul. Finally, you may allow free throws for any baskets that are made [source: Lifetime].