one
Solving the equation of one yuan and one degree is the content of the second section of chapter 3 in the first volume of the seventh grade of People's Education Press. The main teaching goal is to let students solve the linear equation of one variable through the combination of similar items, which is the deepening and promotion of logarithmic operation and the requirement for students' higher computing ability.
The teaching process is as follows: the first step is to introduce the theme with Al-Hualazimi's "elimination and reduction". In the second step, through the exploration of practical problems, the method of solving the linear equation with one variable by combining similar terms is realized. The third step is to let students understand the function of "merging similar items" through "thinking". The fourth step is to master the standard writing of the problem-solving process through the example 1. The teaching situation of this class is reflected as follows.
First, success
1. Creating situations and introducing topics from the history of mathematics can improve students' interest in learning and attract their attention.
2. Through the inquiry and communication of the question 1, students' subjective initiative can be brought into play and their sense of cooperation can be cultivated.
3. The example 1 can standardize students' writing in the process of solving problems and improve their logical thinking ability.
4. Inquiry teaching method creates a relaxed, harmonious and pleasant classroom atmosphere, and students' learning enthusiasm is high.
Second, shortcomings.
1. The content of "thinking" in the textbook is not handled properly. It does not make students realize that merging similar terms is an identical deformation, which makes the equation simpler and closer to the form of "x=a".
2. In the teaching process, when dealing with the problem 1, we don't emphasize the basis of establishing equivalence relation, that is, "the total amount is equal to the sum of the quantities of each part".
3. There are two kinds of similar terms, namely unknown linear terms and constant terms, which are not emphasized enough.
Third, students in the operation of the problems
1. Careless calculation error. Some students are eager for success and careless in calculation, which leads to calculation errors and calculation ability is not up to standard.
2. The calculation process is not standardized. For example, "3x=6" is calculated by some students as 1x=2, and the unknown coefficient can be omitted when it is "1". Some students finally calculate it as "2=x", and the writing format is not standardized.
3. Dependence on calculators. Calculators are often used in large quantities, which reduces the ability of oral calculation and written calculation.
Fourthly, some thoughts on improving computing power.
1. Develop good calculation habits and avoid being careless and eager for success.
2. Pay attention to the standard writing in the process of solving problems and develop good writing habits.
3. Rational use of calculators to improve oral and written calculation ability.
4. Pay attention to the formation process of knowledge, improve problem-solving skills, reduce the amount of calculation and reduce the error rate.
two
This lesson is based on students' learning to use the basic properties of equations to solve linear equations with one variable. But in the process of solving the problem, it is too difficult to write the reason. The appearance of the shift term makes the solution of a linear equation with one variable have a more concise expression and solution, but the shift term is actually the same algebraic expression of the addition and subtraction of the properties of the equations on both sides of the equation, and the result is another way of saying the equation. Therefore, the derivation of the concept of empathy can not be separated from solving the equation by using the properties of the equation, so I designed several problems to solve the linear equation of one variable by using the properties of the equation in the preview, so that students can do them on the blackboard during the break, paving the way for students to explore the concept of empathy independently. Because the focus of this lesson is the application of the law of empathy, I designed several exercise groups to consolidate the concept of empathy, solve problems through group cooperative learning and autonomous learning, and deepen the understanding and application of the concept and law of empathy. Then, teach yourself the examples in the textbook, master the basic steps and algorithms for solving linear equations with one variable, consolidate its application, and let students realize the simplicity of solving problems. Through the application problems in standard tests, let students further understand the importance of solving linear equations with one variable in solving practical problems.
When I design a problem, I want to design a practical problem close to students' life in the new class. Finally, after learning to solve the one-dimensional equation, I asked the students to solve this problem with what they had learned. But considering the time problem, I didn't design it, so I didn't do well enough in strengthening students' application consciousness in learning mathematics.
three
The flow of this lesson: first solve the equation with the properties of the equation, and then introduce the concept of shifting term, and then let the students solve the equation by shifting term. Of course, today is the first time to contact this part, so the combination of similar terms is relatively simple in the choice of equations. Compared with the previous section, we can easily feel the simplicity of this solution. After the explanation, several equations are given for students to practice. It is difficult to observe the students' practice process carefully.
To sum up, there are several common situations in the process of students doing problems: ① I don't know how to deal with the unknown items; (2) the shift project has no sign change; (3) items that have not moved have also changed their symbols; ① and ② have the highest frequency; In view of the above situation, make use of class time to let students with difficulties talk about their difficulties in the process of solving problems, and let other students help him find out the mistakes and solve them, so as to promote mutual progress among students. Then let the students sum up the points and the teacher will guide them. Finally, the general steps to solve the linear equation of one variable are summarized. By summing up, teachers can well see the formation and mastery of students' knowledge.
Generally speaking, although the students summed up their mistakes well in class, their mastery of solving equations is still superficial, and there are too few targeted exercises in class, so the problems in homework come out; First, some students still use the original equality property in solving problems, failing to understand that the process of solving equations is derived from the equality property, rather than a simple repetition of the equality property; Second, symbols are still a big problem when moving objects: when moving objects, some people forget to change symbols, and some people have no concept of changing symbols at all. Although I emphasized it in class, there are still a few students who don't listen and don't translate it into their own knowledge.
As the difficulty of this course, that is, the problem of shifting terms and changing numbers in the process of solving equations, because some students have not mastered it well, there must be problems in some links in teaching. After repeated thinking, I think that although the leading role of teachers has been played, the main role of students has not been well played. The method of shifting items and changing signs should not let students remember concepts, but should let students understand and master them in inquiry. In class, students should have enough time to discuss and practice, and teachers should correct the mistakes that appear in students, so as to achieve twice the result with half the effort and truly master this knowledge point. So on the whole, this course has not really achieved the expected teaching effect. Therefore, in the future teaching, first of all, in the process of preparing lessons, preparing lessons means preparing students, giving full consideration to students and designing problems for the key and difficult points of teaching; At the same time, in the teaching process, we should set aside some time for students to fully discuss and communicate, and give full play to students' subjective initiative in learning; Furthermore, it is necessary to arrange appropriate exercises to consolidate, so as to achieve the expected teaching effect. I think that the unfinished tasks and existing problems in this class should be solved in time in the future teaching, seriously reflect on their own teaching methods and means, feedback students' learning information in time, pay attention to the classroom teaching effect, fully grasp the classroom for 45 minutes, and put forward requirements for the quality and effect of classroom teaching.