Economically disadvantaged preschool children were trained in one of three types of fantasy activities over a school year. One group of children listened to fairy tales, and then acted them out. The children would pantomime such things as the wolf blowing the pigs' houses down, or the pigs running and screaming with the wolf in hot pursuit. The children were encourage to trade roles fromsession to session. Another group of children acted out common experiences, such as visits to the doctor or grocery store, or outings to the zoo, a fire station etc. The stories acted out were thus closer to the children's actual experience and involved less fantasy than those of the first group. A third group of children read fairy tales, but they did not act them out. After hearing the stories, the children would discuss them. In addition to these three groups, a fourth group of children acted as a control group that had interaction sessions with the staff involving such typical preschool activities as finger painting cutting and pasting and identifying animals in picture books. It was found that the physical enactment of fantasy experiences markedly improved children's performance on a variety of measures of intellectual functioning, empathy, length of resistance before touching an attractive but forbidden toy, and other measures of impulse control. Simply listening to and discussing the stories was usually no more effective than the control situation. In addition, the results suggested that fantasy play, which was farther removed from reality, such as that involving fairy tales, had more positive consequences than sociodramatic play dealing with more common experiences. Imaginative sociodramatic play can be used successfully as a means of facilitating cognitive development and self - control in young children. The passage mainly concerns ______.