Here are a couple of great drills designed to maximize your player's ability to dribble and control the ball.
Dribble & Turn - Dribbling
Set up a line of cones with another line about 10 yards away from it. Have the kids dribble to the opposite line, make a turn and return to the beginning. Have them repeat multiple times. You can have them perform different types of dribbles to keep things interesting. Outside of the foot, just right foot, alternating feet, etc.
Number of Players: All
Equipment: Each child needs a ball. 3-5 cones for each line.
Beat Down - Dribbling
Set up an area about the size of the penalty box with a cone goal on each end. Your players will play 3 on 3 with the following condition. You can't shoot unless you take on and beat someone with a one-on-one dribble move.
Number of Players: Groups of 3
Equipment: A ball for each mini-game. Cones for goals.