Sports and games offer students a lot of lessons and values. Other than the fact that sports is good for the health of a student, it also teaches students patience, sportsmanship, and appreciation of hard work. Patience because in order to win games, one has to maintain level headed and cool so that he will not cloud his judgment. Sportsmanship, so that even if one loses, he is not bitter about it and can even congratulate his opponent. And appreciation for hard work because attaining skills is not an easy task.
Probably children between 7 and 9 years old because they have already learned how to read and write but they still have a limited vocabulary range comparing to older people. Also, they do not fully understand written instruction and recreate them in their own minds, the visual cues helpthe written language.