设计理念: “万以内数的乘法”这部分内容,在以往的教学中,一直被视作教学的重点,也是教学的难点。难在哪里呢?难在计算的过程中,在列竖式计算的算式里(乘数是两位数)有两个部分积。这两个部分积,一个是表示多少个“一”,另一个是表示若干个“十”,学生往往在第二个部分积的书写位置上出现差错《全日制义务教育数学课程标准(实验 Design philosophy: “Multiplication within a few million” This part of the content, in the past teaching, has been regarded as teaching focus, but also teaching difficulties. Where is it difficult? In the calculation process, there are two partial products in the column vertical calculation (multiplier is two digits). The two partial products, one is to indicate how many “one”, the other is to indicate a number of “ten”, students tend to write in the second part of the plot error "full-time compulsory education mathematics curriculum standards