David Elkin -"The Wisdom of Play"
I am staying with my son and family in New london, Connecticut, USA. I came across this free (in USA) booklet introduced by David Elkind.
...."Clearly, play serves a very different function for children than it does for adults. For children, it is a way to learn about self and the world through self-created experiences. That is one reason child-initiated play is so important and why it should not be replaced either by adult-organised sports or by academic activities disguised as games."