This is a great drill to teach younger football players the proper way to hand off the football, as well as how to receive a hand off.
Line kids up in 2 lines facing each other. Use cones to designate the beginning of the line. Give the ball to the first child in one of the lines, having him hold the ball the proper way, with 2 hands: one hand/forearm covering the top of the ball and the other hand/forearm underneath the ball.
Have the ball carrier take 2 steps towards the other player, and hand the ball off to him. The player receiving the hand off should have their hands/arms in the proper position to receive the ball: arm closest to the player handing them the ball goes up, and the other arm goes down. As the ball is placed in between their arms have them clamp down on the ball and walk towards the next player in the opposite line.
Once a player has received the ball and handed off to the next player have them go to the end of the opposite line and repeat.