<正>加强估算、培养数感是新课程的基本要求,是中小学数学教学的一个重要内容,也是国际数学教育的改革方向。那么美国的课堂是如何介绍和讲解估算的呢?Most problems you have solved require an exact answer.There are many times,however,when you can estimate(估计) or approximate(粗略估计) a solution.