Reflection on the teaching of the corner

Part 1: Reflection on the teaching of the corner

The angle of the painting is taught after the students have studied the measurement of the angle and the classification of the angle. Before class, I expected that the students' hands-on ability was relatively weak. Therefore, when learning the drawing method, the teacher mainly explained and combined with the explanation of the board, focusing on the student hands-on practice. From the perspective of the effect of the class, it is still relatively good, but there are more problems in the homework, mainly because the painting is not accurate. Some students even draw the obtuse angle into an acute angle, and the sharp angles become obtuse angles. The main reason for careful reflection is that when students draw corners, the internal and external scales are not clearly defined. In the process of painting, students have a lot of internal and external scales. This shows that when they draw the corner, they don’t really think about whether to find the inner scale or the outer scale. Just seeing this degree will immediately make a good point, which will result in an obtuse angle that was originally an obtuse angle. It was originally obtuse. Draw an acute angle.
Based on the above analysis, I think it is necessary to improve my teaching as follows:
1. When recognizing the protractor, it is necessary for the student to know which number of the inner scale corresponds to which number of the outer scale, which is indeed negligent in teaching.
2. Before drawing the corner, students must be asked to know whether they are drawing an obtuse angle or an acute angle. After the painting, they must be tested.

Part 2: Reflection on the teaching of the corner

The "painting angle" is based on the students' intuitive understanding of the angles of acute angle, right angle, obtuse angle, flat angle, circumference angle and master angle. Let the students further experience the definition of the angle and the size of the various corners during the operation of the corner. The knowledge migration point is the use of the protractor--the common point of the angle and the angle, that is, the "two-in-one alignment". The examples of the textbook show the three steps of the painting angle, so that the students can follow the prescribed steps to draw the students' ability to map and let the students experience the use of migration to learn new knowledge, and also for the follow-up learning "vertical And the knowledge of "determining the position of the object" lays the foundation.
The textbook is arranged in such a way that three steps of drawing the corners are presented, allowing the students to follow the prescribed steps. 1. Draw a ray so that the center of the protractor coincides with the end of the ray, and the 0 tick marks coincide with the ray. 2. Click a point on the 65 degree line of the protractor. 3. Draw a ray by drawing the ray and the endpoint as the endpoint and passing the point just drawn. Here, I combine the knowledge before and after, adding a step to the students before the corner: Estimate. First think about how big the corner you want to draw, what angle is it, for example, to draw a corner of 65 degrees, how big is the hand to draw, after painting, then look at how the front is estimated, so that the students will finish painting Check the error yourself after the corner. For example, the confusion of the inner and outer circles, the 65 degrees is drawn to 115 degrees, originally estimated to be an acute angle of less than 90 degrees, and painted as an obtuse angle, it must be a wrong drawing, check the error and correct it. In addition, after painting, I also added another step: check. Then use the angler to measure the angle of the painting itself, and then mark the degree and then the radians and degrees. In this way, the corner is completed.
Through such teaching, not only the correct rate of the corner is improved, but also the students' space concept and good habits are tested in the process. The teaching of this lesson also received very good results.

Part 3: Reflection on the teaching of the corner

I have heard the mathematics of the fourth grade "The Painting of the Corner". I have always felt that the angle of painting is a difficult point in teaching. It is also a difficult point for students. Before class, I carefully thought about the teaching of this knowledge point. In the textbook, I arranged the "category of the corner" and the "painting angle" to teach in the same class, but I think that for my class, this kind of teaching has certain difficulty, so the students can master so much. The knowledge points will definitely be the same as the ones in the class. There will be no opportunities for practical exploration in the class. Therefore, I decided to teach in two lessons, first teaching the "category of the corners" and then teaching the "painting angle".
When classifying the teaching angles, I found that the angle of the painting was very random, especially in the second grade students who had already drawn a right angle, but I found that students rarely use the right angle of the triangle to draw, but draw a ruler with a ruler. At right angles of myopia, even some students directly draw two rays to form a right angle. So in the class, I started from the right angle of the painting and asked the students to say: "In the corners you know, those corners are best painted?" The students quickly proposed the flat, round, and right angles, and then I asked the students to try these paintings. Corner, and let the students show their painting process on the blackboard. After the painting, let the students evaluate and discuss. The students quickly pointed out the advantages and disadvantages of drawing the flat angle and the angle of the week, and collectively made corrections. When drawing a right angle, I intend to find two classmates who use the above method to draw a corner. Then let the students discuss it. "How can I know if the right angle of the painting is normal?" The student proposed to use a protractor or a right angle to the triangle. The student still found that the right angle was not standardized. Not to mention the feeling; then let the students discuss "How to draw a right-angle specification?" With the process of inspection, students can quickly think of two methods. After the students tried, the teacher demonstrated the right angle, and the right angle painting method was standardized.
Then I asked the students to draw a 60° angle, and the students still chose to draw with a triangle. Then I asked the students to draw a 65-degree angle. The students found that they could not be drawn with a triangular plate, which led to the use of a protractor to draw the corners. Finally, I guided the students to summarize the method of drawing the corners of the protractor and discussed: “Draw a corner with a triangle ruler and a angler to draw a corner. Which method is more widely used?” After the students discussed, the use of the protractor was wider, and finally Students try to draw a 75-degree and 100-degree angle with a protractor. Each time, students are asked to cross-check between the same table. Masters are mastered, apprentices and apprentices evaluate together to obtain excellent grades. The students are very enthusiastic. In this way, the students basically master the method of drawing the angle with the protractor.

Part 4: Reflection on the teaching of the corner

"The Corner" is taught after the students have studied "The Measurement of the Corner". Students already know the method of measuring the angle, and they are very interested in the painting method that in turn explores the corner.
Before class, I expected that the students' hands-on ability was relatively weak. Therefore, when learning the drawing method, the teacher mainly explained and combined with the explanation board, and did not let the students explore the painting independently. Put more time on the hands-on practice of the students. From the perspective of the effect of the class, it is still relatively good, but there are more problems in the homework, mainly because the painting is not accurate. Some students even draw the obtuse angle into an acute angle, and the sharp angles become obtuse angles. Careful reflection may be caused by the following aspects:
1. When learning to draw, the teacher's explanation is mainly based on the teacher's explanation. The students are passively accepting knowledge and have not experienced the process of forming knowledge. In the classroom, the students seem to have learned. Actually, because the experience is not profound, the students did not put knowledge. It is well absorbed and internalized, and it is not firmly controlled, so it is not good for homework.
2. The most common mistake of students is to find out the number. This shows that the foundation in front of the students is still not well-played, and the scale on the protractor is still unfamiliar. Especially when it is not ten degrees, it is more wrong. Many students draw less or draw 10 degrees, which means that when they draw the corner, they are not very clear about the range of the degree.
3. When students draw corners, the internal and external scales are not clear. In the process of painting, students have a lot of internal and external scales. This shows that when they draw the corner, they don’t really think about whether to find the inner scale or the outer scale. Just seeing this degree will immediately make a good point, which will result in an obtuse angle that was originally an obtuse angle. It was originally obtuse. Draw an acute angle
4. Some students use a protractor that is not good. Some students have very few tick marks on the protractor. Some protractors have many patterns on the protractor. Some of the protractor center points are a small hole. When the students move left or right when they overlap, there will be a 10 degree error. It also caused interference to students' learning.
5. Some students use the inner circle to draw the angle, there are 5 degrees, such as 75 degrees, can not directly hit the 75 degree position of the inner ring of the protractor, so the position of this point can not be found. They won't look out at the 75 degree position on the protractor, and some will look at the tick marks and deviate to other scales. There are still many students who are not familiar with the number of internal scales corresponding to the number of external scales, so no points can be found.
Based on the above analysis, I think it is necessary to improve my teaching as follows:
1. Before learning to draw, you can give students a certain amount of time for self-exploration, so that they have a certain learning experience. After the process of learning, they will have a deeper understanding and mastery of knowledge.
2. When students purchase the protractor, it is best to choose no pattern on the protractor, the scale is relatively clear, which will be more conducive to the accuracy of the angle and angle.
3. When recognizing the protractor, it is necessary to let the student know which number of the outer scale corresponds to the number of the outer scale, which is indeed negligent in teaching.
4. Before drawing the corner, students must be asked to know whether they are drawing an obtuse angle or an acute angle. After the painting, they must be tested.

Chapter 5: Reflections on the Teaching of Painting Corners

First, the knowledge of the learning angle is not only to explicitly propose the outcome goals that need to be achieved, but more importantly, through the full excavation of the teaching materials, creating contexts, grasping the entry points that effectively stimulate students' active participation and positive thinking, thus forming An experiential goal that helps students develop. In the course of this lesson, I focused on the hands-on operation of the students, and adopted the route of “Drawing Corners – Recording – Summarizing the Corner Method”. Students complete the learning of knowledge in the process of independent exploration, which is intuitive and interesting. Students experience the joy of cooperation in the group's joint activities. Achieved the emotional exchange in the subtle. The realization of the new curriculum standard: "Teachers should stimulate students' enthusiasm for learning and provide students with opportunities to fully engage in mathematics activities. Help them to truly understand and master basic mathematical knowledge and skills, mathematical ideas and in the process of independent exploration and cooperation. Method to obtain a wide range of mathematical experience" requirements.
Second, some students in the activity draw a 60° angle with a 60° angle on the triangular board, and some protractors draw a 60° angle. After the event, I asked the student representatives to show both methods. When the classmates discussed, some students suggested that the 60° angle drawn by the triangular plate is not enough standard, because the sharp corner of the triangular plate is not easy to draw, but another classmate immediately objected, he said, just draw two sides first, then Extending the intersection of the two sides, the corner appears, and it is also very standard. I couldn't help but show my sincere smile when I saw my classmates applauding. In this way, the students agreed that both methods are very good.
In the event, some students used the corner of the textbook to draw at the right angle. I praised the students for their observation and application, and guided them to use the right angle of the triangle to verify. This just shows that learning mathematics uses the materials in life and is closely connected with life.