Since the implementation of "Research on Developmental Classroom Teaching Methods" in 2007, I, as a municipal academic leader and a member of the training team of famous mathematics teachers, have first devoted myself to the research of the subject. Under the guidance of the general subject, I have actively declared the sub-topic "Experimental Research on Developmental Classroom Teaching Methods and Cultivation of Students' Ability", focusing on classroom teaching and improving students' ability, and pursuing the teaching concept and teaching method of promoting teachers and students' active, coordinated and effective development through excellent teaching activities and students' active learning activities. The teaching design of Youduo course is based on the principle of foundation and development, focusing on the problem from the perspective of students' learning, focusing on the way of students' learning, reflecting the research of teaching methods and serving the purpose of students' learning. So as to better promote the development of students. In July, 2007, this class won the first prize of the 9th National Primary School Mathematics Excellent Course Appraisal by the National Academy of Educational Sciences.

I have designed the lesson "How Heavy" many times before and after. From the traditional teaching at the beginning to paying attention to students' all-round development, from passive learning at the beginning to active knowledge later, every progress is arduous, but it is valuable, because this lesson not only contains the results of my repeated practice and reflection, but also permeates a lot of sweat from my colleagues. This lesson will be displayed on the podium of the national competition. So I think this case is worth expressing.

The expression is as follows:

First, create a situation

In order to meet the psychological characteristics of primary school students, arouse their enthusiasm for learning and better participate in learning, I first designed this way to organize students to watch an animated film in which a little monkey and an elephant are on the seesaw. As a result, the little monkey always presses up here, which leads to the concept of light and heavy objects. Then I took out a bag of popcorn that children like and a bag of nails commonly used by workers' uncles. Feel for yourself, and then I asked, "How much do they weigh?" This leads to the topic of "how heavy". Although this design led to the topic, I found that some children were still immersed in the cartoon they just watched. I immediately took out two packages of things, which looked the same in size and could not attract their attention at all. And I only let one child come to the front to feel the weight of these two packages. If other students have no life experience, it is difficult to judge who is light and who is heavy, so it is difficult to integrate into this scene. Based on the above reasons, I redesigned such an exchange scene from the perspective of students: Do you want to be good friends with Teacher Xue? How do you want to express your feelings? "The children's interest was aroused at once. Some people shake my hand, some hug me, and some just kiss my cheek. Then I said, "I also want to express my feelings. I want to hug you, okay? " The children are more excited. I held a child in my arms and asked, "Do you like me? Then come and hug me! "But he just can't hold it. At this time, I asked him to hold my deskmate. He picked up his deskmate with all his strength. I asked, "What is the reason?" "Do you know how much you weigh? Then guess how much I weigh according to your weight? " This naturally leads to this topic. The introduction of this design is to make full use of immaterial teaching methods such as the combination of teachers and students' physical conditions and oral questions, and to make students realize the weight of objects in the process of communication between teachers and students through practical methods suitable for primary school students such as hugging, comparing and guessing, so as to further explore the multiple desires of objects.

Second, feel new knowledge in activities.

1, know the balance in life

With the help of the situation just designed, as a good friend, I brought many gifts to my classmates. I carefully selected pine nuts, egg yolk pie and apples with different qualities in each group of desktop trays. In order to know the weight of these objects accurately, I must use some tools to measure them. I used multimedia courseware to introduce a series of commonly used tools for measuring the quality of objects to students, which broadened their horizons and enriched their knowledge.

2. Establish the quality concept of Gram.

In order to broaden students' experience space, in the process of establishing the concept of gram quality, I boldly asked students to operate by hand and weigh the quality of a coin with a balance. Each group prepared enough coins, and everyone put them in their hands to fully feel the quality of one gram and exchange feelings. After determining the weight of one gram of objects, they will find out which objects are one gram in contact with life. When students can't give accurate examples, I use multimedia courseware to reproduce one gram of things in life in time, such as three peanuts, eight sunflower seeds, five soybeans, three hoop needles and so on. After students have rich appearances, guide them to expand from one gram to two grams, five grams and ten grams, which is getting heavier and heavier. Then, I choose one I like from the teachers' gifts, experience it for myself and estimate the weight. For the packaged egg yolk pie, children with rich life experience can directly understand its quality by looking at the packaging. In this link, students actively construct knowledge, form a superficial understanding of grams through activities such as "weighing, estimating and weighing", and then connect with real life, expand to items that students often touch, feel the mass of several grams, dozens of grams and hundreds of grams, further deepen students' experience in the process of organic combination of cognition and emotion, initially establish a correct concept of quality unit, and at the same time infiltrate learning. In the previous design, I was worried that students would not use the balance and waste time. So I personally demonstrated the quality of a coin and told the students that it was "one gram". Then I organized the students to weigh it and talk about the feeling of one gram in the palm of my hand. After feeling the quality of one gram, when instructing students to give examples of things about one gram in life, because students have just come into contact with the quality unit of "gram", they are not very clear. Because there was no courseware to demonstrate the situation of one gram of goods in life at that time, students did not have a richer concept of one gram of goods. At this time, I ignored it and only focused on the next link. In the next link, I only prepared egg yolk pie, which directly asked students to estimate the quality of egg yolk pie. Because it has been displayed on the packaging bag, students can see it at a glance without hands-on operation. After reflection, I feel that the students' experience of "ke" is not deep enough and the concept is still vague. Therefore, after reflection and discussion, the previous contents are designed and displayed. In my opinion, mathematics in life is not taught by teachers, but experienced by children themselves. Only in this way can we form certain skills and gain positive emotional experience.