This is a dribbling drill that can be done in two lines, or just as partners, depending on the size of your group/team, the gym space, and the number of basketballs available. Start the drill off slowly with emphasis on keeping eyes up and not on the ball then speed it up.  Excellent skill builder.

Partner Dribbling Drill
This description is using the partner method.

Partners face each other across the court, so each partner is on a sideline to begin.
Both players have a ball, and simultaneously, dribble directly toward one another with the same hand.

Once they reach each other in the middle, both players crossover dribble to their opposite hand, then continue on until they reach the opposite sideline from where they started the drill.

Players can do this first beginning with their right hands, then beginning with their left hands.  This forces them to be able to perform a crossover dribble with both hands.

The drill is done slowly at first, until they master control, and keeping their eyes up.

It should progress by gaining speed, as well as crossing over closer to their partners as they become more confident.