小数乘法的计算法则与整数乘法的计算法则基本相同,只是多了小数点的处理问题。因此教学小数乘法的法则时,不必过多地要求学生计算,应把重点放在使学生懂得确定积的小数点位置的方法和道理上。由于学生还没有学过分数乘法,所以现行教材用积的变化规律:“如果一个因数扩大若干倍,另一个因数不变,它们的积也扩大同数倍”、“如果一个因数扩大a倍,另一个因数扩大b倍,它们的积就扩大a×b倍”,来说明小数乘法的算理依据和小 The rules for the calculation of fractional multiplication are basically the same as the rules of multiplication for integer multiplication, except that the decimal point is handled more. Therefore, the principle of teaching decimal multiplication, students do not have to ask too much calculation, should focus on making students know how to determine the product of the decimal point position and reason. Since the students have not yet learned the fractional multiplication, the current teaching material uses the law of product variation: “If one factor is multiplied several times and the other factor is constant, their product also expands several times.” “If a factor is multiplied by a factor, Another factor to expand b times their product to expand a × b times ”to illustrate the mathematical basis of fractional multiplication and small