Kids can play more complex games now.  They are better at problem-solving and can often 
follow complicated directions.  They'll choose their play based on their interests in different 
sports/activities.  They follow the rules more readily because they can now understand how 
structure adds to their safety and enjoyment of the game.  But they also want to express their
individual  personalities; they become more deeply involved in hobbies of their own choosing.  
They have more dexterity to handle toy pieces and parts carefully, and their longer attention 
span makes it more likely that they'll finish projects.