"The worst thing one can say to a child when aiming a camera at him is, "Act naturally". That will shrivel him on the spot. Children are natural actors but you must give them something to act. However many children you are going to film, give each one a separate identity. Tell the little boy to pretend the bicycle is one he has just won in a competition. Tell the little girl she is a princess in disguise. Give them something to work with and think about before the filming begins. Watch how one boy flicks his hair or rubs his nose, how a girl twists her braids and rubs one foot behind her leg. How they eat, how they smile, how they show shyness or jealousy by jumping up and down or pouting in a certain way. Then, when you are ready to film, re-enact their own mannerisms to them and ask them to imitate you. In fact, they will be doing what comes naturally to them."
Carol Reed