A On average, American kids aged 3 to 12 spend 29 hours a week in school, eight hours more than they did in 1981. They also do more household work and participate in more of such organized activities as soccer and ballet(芭蕾舞)．Taking part in sports, in particular, rose almost 50% form 1981 to 1997: Boys now spend an average of four hours a week playing sports; girls log half that time. All in all, however, children’s free time drops from 40% of the day in 1981 to 25%. A On average, American kids aged 3 to 12 spend 29 hours a week in school, eight hours more than they did in 1981. They also do more household work and participate in more of such organized activities as soccer and ballet(Bellelist). Taking part in sports, in particular, rose almost 50% form 1981 to 1997: Boys now spend an average of four hours a week playing sports; girls log half that time. All in all, however, children’s free time drops from 40% of The day in 1981 to 25%.