2、挖掘教材资源，体验估算的重要地位。翻开新教材,我们不难发现，估算已

2. Explore the resources of teaching materials and experience the important position of estimation. Looking at the new textbooks, it is not difficult for us to find that estimation has left a deep footprint in many areas of mathematics textbooks. As long as we handle the textbooks creatively, estimation is everywhere. In the field of number and algebra: the calculation teaching combined with addition, subtraction, multiplication and division can cultivate the awareness and ability of estimation in each class. For example, 4812 + 12, students are likely to miss the 0 in the quotient when calculating. If you estimate first, 4800 + 12 = 400, so the quotient of 4812 divided by 12 must be more than 400, which not only avoids calculation errors, but also cultivates The students' consciousness of making estimates consciously before calculation. In the field of space and graphics, "Mathematics Curriculum Standards" clearly pointed out: can estimate the length of some objects, estimate the area of ​​a given rectangle and square, estimate the surface area and volume of a given three-dimensional figure, and so on. In the field of statistics and probability, combining data collection and sorting, understanding statistical charts, estimating the size of possibilities, and so on. <br>3. Cultivate mathematical thinking and experience the mathematical value of estimation. Estimation teaching can also train students' flexibility in thinking, make students' thinking more flexible, draw inferences about problems, learn by analogy, and transfer their thinking to a more hidden direction that is not easy for others to think of. For example, when comparing the sizes of 12/25 and 19/35 in teaching, some students think of passing points when they see that the larger and smaller ones are different denominators. In fact, this question does not need to pass points, as long as you estimate: 12/251/2, you can judge 12/25

2. Mining textbook resources and experiencing the important position of estimation. When we open the new textbooks, it is not difficult to find that estimation has left a deep footprint in many fields of mathematics textbooks. As long as we deal with textbooks creatively, estimation is everywhere. In the field of number and Algebra: combined with the calculation teaching of addition, subtraction, multiplication and division, each class can cultivate the estimation consciousness and ability. For example, 4812 + 12, students are easy to miss the 0 in the quotient. If they estimate first, 4800 + 12 = 400, so the quotient of 4812 divided by 12 must be more than 400, which not only avoids the error of calculation, but also cultivates the students' awareness of consciously estimating before calculation. In the field of space and graphics, the mathematics curriculum standard clearly points out that it can estimate the length of some objects, estimate the area of a given rectangle and square, estimate the surface area and volume of a given three-dimensional figure, and so on. In the field of statistics and probability, combined with data collection and sorting, understand statistical charts, estimate the possibility, etc.<br>3. Cultivate mathematical thinking and experience the mathematical value of estimation. Estimation teaching can also train students' thinking flexibility, make students' thinking more flexible, draw inferences from one example, bypass by analogy, and transfer their thinking to a more hidden direction that others are not easy to think of. For example, when teaching compares the size of 12 / 25 and 19 / 35, some students see that the comparison size is different denominator and think of general score. In fact, there is no need to divide this question. As long as you estimate: 12 / 251 / 2, you can judge 12 / 25

2. Excavate teaching material resources and experience the important position of estimation. Turning over the new textbooks, we can easily find that estimation has left a deep footprint in many fields of mathematics textbooks. As long as we deal with textbooks creatively, estimation is everywhere. In the field of number and algebra: the teaching of calculation combined with addition, subtraction, multiplication and division can cultivate the awareness and ability of estimation in every class. For example, 4812+ 12, students tend to miss 0 in the middle of quotient when calculating. If we estimate it first, 4800+ 12=400, so the quotient of 4812 divided by 12 must be more than 400, which not only avoids calculation errors, but also cultivates students' consciousness of consciously estimating before calculating. In the field of space and graphics, "Mathematics Curriculum Standard" clearly points out that it can estimate the length of some objects, the area of given rectangle and square, the surface area and volume of given three-dimensional graphics, and so on. In the field of statistics and probability, combined with data collection and collation, we can recognize statistical charts, estimate the possibility and so on. 3. Cultivate mathematical thinking and experience the mathematical value of estimation. Estimation teaching can also train the flexibility of students' thinking, make students' thinking more flexible, draw inferences from others' mistakes, and transfer their thinking to a more hidden direction that others can't easily think of. For example, when comparing the sizes of 12/25 and 19/35 in teaching, some students think of a general score when they see that the comparison size is different from the denominator. In fact, this question can be judged as 12/25 as long as it is estimated as 12/251/2.