一、问题的提出“分米和毫米的认识”这部分内容是在学生认识长度单位米和厘米,有了一定的用尺度量长度的经验之后进行教学的,要求学生在活动中认识分米和毫米,建立表象,并能理解整合后的各个长度单位,掌握米、分米、厘米和毫米之间的进率关系。随着社会进步,经济技术发展,如今信息传播渠道多元,学生见多识广,分米和毫米这两个长度单位对他们来说早已不陌生,虽然没有系统的学习过,但是听过、看过的学生一定不在 First, the question put forward “Understanding of decimeter and millimeter” This part of the content is the students know the length of meters and centimeters, with a certain amount of length and length of experience after teaching, requires students to recognize points in activities Meters and millimeters, build an appearance, understand the integrated length units, and master the rate of advance between meters, decimeters, centimeters, and millimeters. With the progress of society and the development of economy and technology, there are many channels of information dissemination and students are well informed. The two units of decimeter and millimeter have long been familiar to them. Although they have not systematically studied, they have heard and looked at Excess students must not be here