In American,primary school pupils are always happy.Every day,children come back home with an empty bag.Their homework is

In American,primary school pupils are always happy.Every day,children come back home with an empty bag.Their homework is only two pages at most.Some of them can finnish it in ten minutes at school,so children there feel happy all the time.
There are about twenty puils in each class.They are in different groups.Different groups may have different textbooks.The whole grade graduate at the same time,but the students learn different knowledge and skill.
The subject they learn include reading,math,language,social sciene,music,art and PE.Their school report cards only show three grades：G means satisfactory,N means you need to work hard.
英语翻译,不要翻译器的,翻译器的我都看过了,都不好