Algebra is the second section of the third chapter of the experimental textbook for the seventh grade of compulsory education (Beijing Normal University Edition). The teaching of this class is a research class. At the beginning of the class, go straight to the subject, reveal the meaning of algebra and algebraic values, and let students review 4+3 (X- 1) and X+X+(X-65438). ..... and so on. The actual background of these formulas and the number of matchsticks in 4+3 (x- 1) when x = 200. After students have these foundations, they will not be unfamiliar with column algebra and evaluation, and then lead to the "normal" column algebra and evaluation problem of example 1, and give the actual background; So, what is there to say about the algebraic expression "10x+5y"? Made a comprehensive and extensive exploration, students from the means of production, daily necessities, geometric objects; Stand still; All these factors lead to the meaning of algebraic expression "10x+5y" in practical or geometric background, which enables students to expand their thinking through mathematical methods such as association, analogy and induction.

Through Example 2, this paper introduces a mathematical problem related to the familiar animal-cricket in students' life: the relationship between the number of crickets chirping at 1 and the temperature at that time, so that students can learn how to assume the algebraic method of letter series in relaxed and happy teaching activities, expand their thinking and activate the classroom atmosphere.

In the classroom practice, give different levels of questions and ask students at different levels, and students at different levels answer well.

Next, I review the teaching of this class, and I have succeeded in the following points:

First, grasp the teaching materials according to the curriculum standards. The new curriculum standard requires us to dilute the concept and pay attention to the formation process of knowledge. For example, the concept of algebra is introduced on the basis of students' existing knowledge, so that students can learn naturally and easily. When learning the example 1 and the following "think about it", let students fully observe, think, analyze and discuss, and help students learn new things through constant error correction, induction and innovation.

Secondly, the significance of algebraic expression "10x+5y" in practical or geometric background is introduced, which stimulates students' interest in learning and makes them feel that real life can not be separated from mathematics, thus further mobilizing students' enthusiasm for learning mathematics.

Thirdly, in the whole teaching process, the student-centered teaching concept is embodied, and teachers are only participants and guides in teaching activities. Regardless of case 1 or case 2, student activities always occupy a major position.

Fourth, arrange different levels of questioning content in classroom practice, so that students have a sense of accomplishment, fully reflect humanistic care and face all students.