As a selfless people's teacher, we should prepare our speeches carefully. How to write the speech? The following is the draft of the lecture on junior high school mathematics circle I collected for your reference, hoping to help friends in need.

Junior high school mathematics round talk about course draft 1 1. Talking about teaching materials:

"Understanding of Circle" is the content of Unit 4 in the first volume of Grade 6 of People's Education Press. It is the initial knowledge of geometry, not only the initial course, but also the basis for subsequent study of "circumference", "area of circle", "cylinder" and "cone".

"The Understanding of Circle" is taught on the basis that students have learned the understanding of straight line and area calculation, and have a preliminary perceptual understanding of circle. Students have changed from learning linear graphics to learning curve graphics, whether it is the content itself or the method of studying problems. Through the study of circle, the textbook enables students to understand the basic methods of learning curve graphics. At the same time, it also permeates the relationship between curve graphics and straight line graphics. This not only expands students' knowledge, but also enters a new field in the concept of space. Therefore, through the understanding of the circle, students can not only deepen their understanding of the surrounding things and improve their ability to solve simple practical problems, but also lay a good foundation for studying the circumference, area, cylinder and cone of the circle in the future.

Second, tell the teaching objectives:

Combined with the characteristics of this class, I have determined the following teaching objectives:

1. Knowledge and skills: by drawing a picture, folding, measuring, etc. Observe and experience the characteristics of a circle, know the names of each part of the circle, and understand the relationship between the inner diameter and radius of the same or equal circle. Understand and master a variety of methods of drawing circles, and learn to draw circles with compasses initially.

2. Process and method: Through imagination and verification, observation and analysis, hands-on operation, cooperation and communication, students can realize the distribution uniformity and extensive symmetry of each point of the circle, and at the same time, their thinking can be further developed and improved.

3. Emotion, attitude and values: Experience the close connection between mathematics and daily life in combination with specific situations, and explain simple phenomena in life with circular knowledge.

Third, the key points and difficulties:

Teaching emphasis: Understand and master the characteristics of circles, and learn how to draw circles with compasses.

Difficulties in teaching: understand the concept of "on the circle" and summarize the characteristics of the circle.

Teaching preparation:

Student: Scissors, some white paper, crayons, compasses, rulers and a round object.

Teacher: Courseware, compasses, rulers, circular pieces of paper.

Fourth, speaking and learning methods:

Teaching methods: In this course, we should pay attention to the changes of students' learning behavior and the development and utilization of curriculum resources. From appreciating and discovering the circle, students are deeply attracted. In classroom teaching, we should pay attention to mobilizing students' multiple senses to participate in learning, and guide students to experience a complete process of "research and discovery" through students' independent exploration, cooperation and sharing. Teach students to learn the law: appreciate the charm of the circle in the situation-explore the characteristics of the circle in cooperation-experience the mathematical culture of the circle in introduction-feel the mathematical value of the circle in practice, boldly let go, and give students all opportunities to explore. Students are not only relaxed and lively in learning, but also can better reflect the teaching concept of the new curriculum.

Fifth, talk about the teaching process.

For the teaching of this class, I have carefully designed two main links.

(A), create a situation, the introduction of new courses

Which graphic characters have we made friends with before? What lines are these figures surrounded by? Briefly describe the characteristics of these figures.

(B), highlighting the main body and exploring new knowledge

1, initial perception circle

First of all, I will ask students to give examples from life. "Which objects are round in daily life?" Students may say: coins, CDs, road signs, clock faces, wheels, etc. These objects are all round. Let students initially perceive the circle and cultivate their spatial imagination. At the same time, I will show some pictures of circles in life, so that students can feel that circles are around us.

Then, I'll show you two sets of numbers. The first group is rectangle, square, triangle, parallelogram and trapezoid, and the second group is circle. By comparison, it can be clearly seen that the first group of figures is surrounded by line segments end to end, while the circle is surrounded by curves, forming a correct representation-the circle is a curved figure on the plane.

Show the pictures of the circle and the names of each part through the courseware. At the same time, according to the courseware pictures, let the students analyze what the circle refers to, inside the circle, outside the circle and the center of the circle. I explain at the right time to deepen students' understanding.

2. Know the names and characteristics of each part of the circle.

Activity 1: group cooperation exploration

(1) Work in groups of four and draw a picture together. What did you find? And communicate in groups.

(2) Prepare to share your findings with you.

(1) Find the center of the circle

First, let the students fold the round paper prepared in advance and open it. Draw a crease with a pen and ruler, and repeat the origami activity on the round paper two or three times. After the operation, ask, "What did you find?" After the students did it themselves, they found that all the creases would intersect at one point. The intersection of these creases is right on the center of the circle. We call this point the center of the circle mathematically, and it is represented by the letter "O". (Design intention: Through students' intuitive operation, students' learning process will be "action-oriented", and students' multiple senses will be mobilized to participate in learning, and some cognitive conflicts will be deliberately set up to enable students to actively participate in the formation of knowledge. )

(2) Know the radius and diameter

The line segment connecting the center of the circle and any point on the circle is called radius, and the radius is generally represented by the letter R.

The line segment passing through the center of the circle with both ends on the circle is called diameter, and the diameter is generally represented by the letter D. Because the knowledge of radius here is the foundation, I will try my best to let students discuss the knowledge of diameter in groups.

Activity 2: Work together.

1 Please draw the radius on the circular paper in 10 second. How many lines can you draw? What about the diameter?

Please measure the radius with a ruler. How many centimeters is it? What did you find? What about the diameter?

Please discuss in groups of four what are the characteristics of the radius inside the same circle? What are the characteristics of diameter? What is the relationship between them? Through measurement and comparison, let students understand and master the relationship between radius and diameter in the same circle, and let students use a formula with letters to express the relationship between radius and diameter. The letter formulas of d=2r and r=d/2 are obtained, and the corresponding relationship between radius and diameter in a circle is emphasized by filling in the table in the exercise. Students are also required to find out the radius and diameter of some line segments in the circle. (Design intention: Give full play to students' main role reasonably, and let students explore the formation and development of knowledge independently with their brains, hands, mouths and eyes, so as to consolidate their learning achievements in time. )

Oral answer:

3, master the method of drawing a circle

In the process of teaching circle drawing, I will also let students use their brains boldly and explore different methods of circle drawing. On the basis of textbook knowledge, I will extend outward. I will ask my classmates: What methods and tools did they use to draw circles just now? Can you share your experience with us? Students can speak different methods and tools, such as coin lines, pens, compasses and so on. At this time, I will pretend to be very anxious and ask the students: The teacher wants to draw an 8 cm circle, can I use a dollar coin? Why? Student: The student union will explain that the size does not match or something. At this time, I will say, I want to draw a 6 cm circle. What should I do? Why? Student: It may be more difficult (I slowly guide students to draw a circle with compasses from the point of view of size and convenience). Then I come to a conclusion that we usually draw circles with compasses. It also shows the process of how to determine the radius of compasses and how to draw circles with compasses (and draws the conclusion that circles with different sizes can be drawn with compasses, and we can also get the circles we want. It is proved again that the larger the radius, the larger the circle, the smaller the radius and the smaller the circle.

Finally, according to what I have learned above, I have prepared two exercises to deepen my knowledge for my classmates. One is to ask students to draw a circle with a radius of 2 cm with compasses, and mark its center, radius and diameter with letters O, R and D respectively. 2. Draw a circle with a diameter of 4 cm.

Practical application: The school track and field sports meeting will be held soon. Can you help the school draw a circle with a radius of 10 meter on the playground? I will consolidate it in time, and link the historical materials on the basis of what I have learned, such as the knowledge about the circle, famous sayings and aphorisms, etc. And through the courseware display, let students realize the historical and cultural accumulation contained in the circle, stimulate students to learn mathematics, use their enthusiasm for mathematics, have a great connection with life in the future mathematics study, and let students feel success and happiness in solving practical problems in life. Learn mathematics, use mathematics, mathematics is everywhere.

Consolidation exercise

1, fill in the blanks.

Ask the students to review what they have learned in this lesson and test their mastery of what they have learned. )

2. Judge and tell the reason.

These problems further deepen the understanding of the circle and cultivate students' ability of analysis, reasoning and judgment. )

Blackboard design:

Understanding of circle

Tuloue

Center of radius r and diameter d

D=2r or r=d/2.

Compass draws a circle: the radius is fixed, the center of the circle is fixed, and it turns once.

Lecture notes of junior high school mathematics circle 2 I. teaching material analysis

The understanding of cylinder is the content of Unit 2 of Volume 15, an experimental textbook for full-time schools for the deaf. Cylinder is a common geometric solid figure, including the characteristics of cylinder, the names of various parts of cylinder and the side development diagram of cylinder. Teaching this part is conducive to developing students' concept of space and laying a good foundation for further studying the lateral area, surface area and volume of cylinders and solving practical problems.

Second, the analysis of learning situation

Because the eighth-grade students in deaf schools have initially acquired a certain self-study ability, they can discuss with each other on the basis of their existing knowledge according to the specific situation, so I use hands-on operation, autonomous learning, cooperative inquiry and other methods to acquire new knowledge in this class. Using multimedia courseware to break through the difficulties of this course. At the same time, in view of the characteristics of deaf students' hearing impairment and relatively backward language development, we should pay attention to deaf students' language training in class, adopt bilingual teaching, encourage deaf students to speak independently and develop deaf students' language.

Third, the teaching objectives

1, knowledge and skills target

Make students know the names of each part of the cylinder, understand the side development diagram of the cylinder and master the characteristics of the cylinder.

2, process and method objectives

Through observation, imagination, operation, discussion and other activities, cultivate students' ability of independent inquiry, hands-on practice and cooperative innovation; At the same time, the idea of infiltration and transformation.

3. Emotion, attitude and values goals

Using the teaching situation provided by the courseware, students can intuitively feel the side expansion diagram of the cylinder and preliminarily see through the dialectical view of the development and change law of things. And let students feel that mathematics is closely related to their own lives and experience the value of learning mathematics.

Teaching emphasis: master the characteristics of cylinder.

Teaching difficulty: understanding the characteristics of cylinder side expansion diagram.

Fourth, the teaching content and process

In this class, I used practical methods, courseware demonstration, group discussion method and other related teaching methods. Teachers only guide students to actively participate in the whole learning process as organizers and guides, and fully mobilize students' enthusiasm for inquiry in the process of interaction. So I carefully designed the following links.

(A) create a situation to stimulate interest in the introduction

1. Open the multimedia courseware and show the physical model of the cylinder. At the same time, feel some concrete objects in life and let students understand that mathematics is in life.

Through the above teaching, let the students get in touch with the cylinder initially, feel the cylinder from the real life and feel the close connection between mathematics and life. At the same time, introduce topics skillfully and naturally to pave the way for learning new lessons. )

(B) independent inquiry to understand the cylinder

1, students learn independently and know the names and characteristics of each part of the cylinder.

Teacher's guidance: take out your own prepared objects and combine them with the teaching materials. Think about the names of the parts of the column by looking and touching. What are the characteristics?

2. Health report, revised by the teacher. Describe the characteristics of each part of the cylinder through the students' language and verify it through the teacher's courseware demonstration. (Class record)

In view of the characteristics of deaf students' inattention, I let students explore independently and provide their own teaching materials, which can quickly stimulate students' interest in exploration, make psychological preparations for exploring new knowledge, and use courseware to verify their ideas. Demonstrate the bottom, side and height of the cylinder, so that students can perceive the names and characteristics of each part at a glance, which can more effectively stimulate students' interest in observation and improve their attention. )

(C) cooperation and exchanges to deepen understanding

1, cooperative exploration, cylinder side expansion.

(1) Students work in groups: cut the side of the cylindrical model, unfold it and observe the shape.

(2) Teacher: How did you cut it? What figures did you get after the expansion?

(3) Students report after homework, and teachers verify and supplement through courseware. (Class record)

This link is carefully designed, so that students can become the masters of learning, and through students' cooperative exploration, students' sense of ownership in mathematics classroom can be reflected. At the same time, through the demonstration of multimedia courseware, the evolution process of different cutting methods of cylindrical edge is shown, which is easy to understand and makes students easily understand the characteristics of cylindrical edge. )

2. Companions help each other and seek discovery.

(1) Let the students get the length-width relationship of the unfolded rectangle and cylinder in the hands-on operation.

(2) Verify the teacher's courseware demonstration expansion diagram, and easily break through the difficulties of this lesson. (Class record)

Let students find, discuss and solve problems in cooperation, and stimulate students' thirst for knowledge. At the same time, through visual courseware demonstration, it is easy to disperse the difficulties of this lesson and highlight the key points of this lesson; Arouse students' enthusiasm. )

(D) consolidate and expand, extend the application

Courseware demonstration:

1, which of the following objects is a cylinder?

2. Point out the bottom, sides and heights of the following cylinders.

3. Actually measure the circumference and height of the cylinder bottom.

The design of the exercises includes the application of the cylinder knowledge just learned, as well as confusion and mistakes, so that students can judge by gestures and dare to speak and debate in a relaxed atmosphere. While training reasoning ability, it also trains students' thinking. )

(5) summarize independently and enhance the concept.

Teacher: We have a preliminary understanding of cylinders. Who can tell the teacher what you know about cylinders?

This is not only a summary of the classroom, but also an important embodiment of the cultivation of students' humanistic quality. Let students develop their expressive ability at the same time. )

Verb (abbreviation of verb) application of educational technology

As a means of education, information technology is increasingly applied to classroom teaching, which can not only create certain situations, but also mobilize students' enthusiasm and highlight the teaching effect. Flash courseware is often used by teachers because of its powerful demonstration function and obvious animation effect. In this class, I demonstrated the relevant knowledge in the form of animation with flash courseware, which runs through the whole class. At the beginning of the class, I made a courseware demonstration of the bottom, side and height of a cylinder, so that students could clearly perceive the names and characteristics of each part. Let the students get interested in this class at the beginning. The class shows the evolution process of different cutting methods of cylindrical edges, which is easy to understand, allowing students to easily understand the characteristics of cylindrical edges and easily break through difficulties. At the same time, on this basis, the relationship between expanded and unexpanded cylindrical edges is displayed for students to see at a glance. In a word, the application of information technology in classroom teaching can better achieve teaching objectives and achieve better teaching results.

Evaluation and reflection on intransitive verbs

Curriculum standards point out that we should not only pay attention to students' learning results, but also pay attention to students' learning process, and pay more attention to students' emotions and attitudes in the process of activities. This course is based on students' existing life experience, from physical observation to hands-on operation. Through imagination, description, cooperation and communication, students can understand cylinders, and use multimedia courseware to disperse difficulties and break through key points in time and effectively, so that students can master what they have learned in a relaxed and happy atmosphere and highlight the mathematical concept of "doing mathematics". It also enables students to make progress in cooperation and experience success.

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