A Research On The Present Situation Of Numerical Estimation For 5-7 Grade Students

With the development of science and technology, as well as the rising popularity of computational tools (such as calculators, computers and so on), these not only change the way people live, but also change the way people calculate. In the past, we calculated by hand. Now we can use tools and get results in a short time. So it's particularly important to judge whether the results are correct and reasonable or not. However, the students in the primary and middle school, because of the frequent use of calculator, lose their ability of manual computation and oral arithmetic day by day. And it's seldom for them to judge if the computational results are correct. Therefore, this is one of the most important reform on education: how to improving the student's estimation ability.This paper discusses the consciousness of computational estimation strategy and problems of Grades 5-7 students. Throughout the whole research, a questionnaire survey on 405 students of Grades 5-7 has been carried on, together with a test on 60 students and some interviews in groups among 6 teachers and 18 students. Finally, we got the following conclusions:For most students, their awareness of estimating are very weak, and also their abilities of estimating are not good enough which manifest mainly in the following five aspects. First, their understanding of the word"estimate"is quite superficial. Second, their knowledge of estimating strategy is partial. Third, their acquaintance of the estimating results is not deep enough. Fourth, they can't make full use of their estimating consciousness and abilities. Finally, they are lack of the experience of estimating resources.In one word, on the basis of the conclusion of this paper, the writer gives the primary and middle schools some suggestions on the curriculum, the trend of teacher education and estimating teaching of mathematics.