“不含括号的两步计算混合运算”原来是苏教版四年级上册的教学内容,现新教材将其下放至三年级下册,笔者起初有些担心三年级的孩子适应不了,但细细想来从学生已有的认知经验和认知发展水平来看,新教材在安排上并不冲突,可是从练习上来看出现了不少问题,以下列举一些学生在作业中的典型错例子: “No bracketed two-step calculation of mixed computing ” The original is the fourth grade of the Soviet version of the teaching content, the new textbooks will be decentralized to the third grade, the author at first some worried that the third grade children can not adapt, but the fine Consider from the students’ existing cognitive experience and cognitive development level, the new textbooks do not conflict in the arrangement, but from the practice point of view there are many problems, the following list some typical examples of students in the homework: