The title of this lesson is: classification and drawing of angles. Includes two parts:

Classification of 1. Angle In this part, students should learn that acute angle is less than 90 degrees, right angle is equal to 90 degrees, and obtuse angle is greater than 90 degrees and less than 180 degrees. On this basis, they should know the straight angle and the rounded corner, master the multiple relationship between the right angle, the straight angle and the rounded corner, and judge the type of the angle by the degree of the angle, among which the determination of the degree range of the obtuse angle is a difficult point. Students can correctly identify acute angle, right angle and obtuse angle when they contact angles from grade two. But at that time, it was obtained by observing the comparison between figures and triangles. I think these are mainly based on image thinking. The content of this section is based on the above, so that students can learn to judge what an angle is by the degree of angle, which is a process from image thinking to abstract thinking. In the design, I use the measurement angle that students have just learned to introduce a new lesson, so that students can judge what the eight angles are through observation. At the same time, I use multimedia to hide the angle graphics and turn them into words. Here students can experience the process from form to writing. In the teaching of the difficult point "the range of obtuse angle is between 90 degrees and 180 degrees", I estimate that most students will think that an angle greater than 90 degrees is an obtuse angle, but I didn't stay here much, but showed the students that the straight angle is 180 degrees with the activity angle. Then let the students compare the size with the obtuse angle and the flat angle, so as to get the correct degree range of obtuse angle.

2. Drawing angles This part is mainly to let students learn to draw angles of any degree. There are two tools that can be used to draw angles: triangles and protractors. At the same time, let the students understand that triangles have their limitations and can only draw some angles with special degrees, while protractors can draw angles with any degree. In this part of the teaching, according to the above knowledge, I let the students know the angle first, and then draw a 60-degree angle. This is a special angle. You can draw it with a triangle and a protractor, and then ask the students to draw a 50-degree angle. At this time, the students realized that the triangle version can only draw some special angles and ask questions from different angles, while the protractor can draw any angle we have learned.

Teaching reflection

1. The guiding ideology of teaching is that students are an individual with subjective initiative, not a pocket. So we can't just cram knowledge into our heads and give students a good direction. We should attach importance to the development of their practical ability and students' thinking ability. Therefore, in the process of teaching, we should pay more attention to inspiration, not only tone, but also questions. For example, at the beginning of the second part, I showed: 60 degrees, 70 degrees, 135 degrees, 90 degrees, in order to let students judge what angle this is, but I think this limits students' thinking. We can ask this question: What can you think of when you see the degrees of these angles on these screens? This broadens the students' thinking, makes the knowledge just now automatically demonstrated in their minds, and helps students to understand and consolidate. I have a misunderstanding about the importance of writing on the blackboard. This class made me realize the importance of writing on the blackboard. Maybe it's because my chalk handwriting is not very good, and I'm afraid to write it on the blackboard, thinking that it's enough to display it on the screen as much as possible, but it's not effective. In ordinary classes, the importance of writing on the blackboard is more prominent. I think I will write more efforts on the blackboard in the future. I should pay attention to the rationality and ingenuity of design and the neatness of writing.

2. Through the specific operation in the teaching process of this class, I further realized the meaning of the word "strict teacher". Teachers must be strict, especially in class, so that students can sit still, don't move, don't communicate at the same table, and don't make small moves, so as to lay a good foundation for everyone to listen carefully in class. With such a good atmosphere and environment, the teaching effect and students' psychological pleasure will be improved to a new level. I will aim at the inferior quality and continue to work hard. But inseparable from the above, the teacher's class should be wonderful and vivid, which can fully mobilize the enthusiasm of students. This requires teachers to make more efforts in preparing lessons and have a comprehensive and clear grasp of the teaching materials, the knowledge that students should learn and the degree to which they should learn. This is also a goal of my efforts.

3. To what extent should multimedia courseware be used in teaching? I used to think that computer courseware is omnipotent in teaching activities, and teachers only need to click it. From the beginning of this semester, I gradually realized that multimedia courseware is only a teaching tool and has its limitations. Teachers are the main body of teaching. If you only use multimedia, you don't need a teacher, just let the students watch TV. Multimedia courseware can help us demonstrate some things that ordinary teaching media can't demonstrate, and it can improve students' interest in learning, which is its advantage. Proper use of multimedia courseware is helpful to improve the teaching effect and students' interest in learning, otherwise the effect will be counterproductive. We should grasp this degree well.

4. Summary and sublimation of trivial knowledge Learning mathematics is not only to let students learn some knowledge, but also to let students learn some abilities and ideas. Therefore, in the teaching process, we should be good at grasping the effective resources generated in the classroom, summarizing them, and constantly subliming students' understanding of new knowledge.