Problem with son's attitude in school.

It is simple to teach him. Had the teacher tried "Do not repeat it please." That's all that they must say. He's a good boy and understand simple instruction. But how can a boy follow an instruction if it is not even told to him?

This could be... for a few reasons. If he cannot explain this reason, perhaps it is the teaching methods or a personal trait of this teacher or some underlying cause. I might suggest speaking to the parents of other children in his class about the matter... see if their children have any strange or interesting things to say. Perhaps have a private meeting with this teacher. After having the private meeting with the teacher, perhaps one between the teacher, your son, and you. Talk to the school principal about observing this class for yourself once or twice. Sometimes kids just don't like their teachers.. regardless of whether they have a valid reason or not. Other times, their teachers have habits or traits that seem odd to them. On a darker note, sometimes it's raw, primal instinct. I had a substitute teacher once who was around our school for several months. Very few people truly liked him. The ones who did were all boys, and mostly boys with mental/emotional problems. When he taught my class, I began to notice his subtle preferences for the boys over the girls. When I moved to another town, he was the preacher at my church.... his attitudes there, I noticed, were the same on a bigger magnitude. Two years later it all came out why: He had been sexually abusing at least one boy that attended the church and my schools, and countless others admitted that he had tried to make advances at them. My gut instinct knew all along something was not right, but no one would listen. They just assumed that I had some sort of personal vendetta.