正负数的教学是初中代数中的一个难点。现行初中代数课本里,是从相反意义的量来引入的。这样做虽然学生易于接受,但是如果没有在运算中讲清道理,学生由于难以理解它的意义,反而不去思考,而是强记,其结果必然会影响教学效果。 The teaching of positive and negative numbers is a difficult point in junior high school algebra. The current junior high school algebra textbook is introduced from the opposite sense. Although this is easy for students to accept, if students do not understand the reason in their calculations, because students cannot understand its meaning, they will not think about it, but will remember it. The result will definitely affect the teaching effect.