立足学生原有认知结构 重构有理数加减运算

Have a Foothold on the Students Original Perception Organization and Set up the Operation of the Addition and Subtraction on the Rational Number

有理数加减运算一直遵循着固有模式,学生对有理数加减的思维与现行教材模式存在不一致的问题.依据建构主义教学理论,重新构建有理数加减运算,应将加号与正号,减号与负号的统一作为切入点,从发展小学加减运算,比较相反数的求法及“ +” 可省略中归纳得出添(去)括号法则,并运用交换律,添(去)括号法则,实现有理数的加减运算向小学加减运算转化.

The operation of the addition and subtraction on the rational number alwayed follows the proper mode. This text started with an inquiry into the differentiation between the students thought about the operation of the addition and subtraction on the rational number and the current teaching mode. The bracket rule of “add” or “eliminate” could be induced by developing the operation of the addition and subtraction of the primary school, comparing the key method of the opposite number and “+” bridged.