Reflecting on the teaching of "area of circle" 1 "area of circle", let students actively participate in the whole process of knowledge formation, improve students' mathematical thinking ability of inductive reasoning, give students the initiative to learn, and let learning problems naturally generate, and you will find how broad children's thinking is. In the classroom, if teachers turn the concept of the new curriculum into actual teaching behavior, sometimes they will realize what is called "unintentional willow planting".
1, put forward the teaching objectives before class.
Teaching objectives help students to clarify the teaching intention of this class and stimulate their learning needs, so as to better participate in learning activities. In the lecture tour of two classes, I deeply realized this. When I asked, "What problems do you think we should solve in this course after seeing the topic?" The student made an offensive speech: "I want to solve how to calculate the area of a circle;" How to deduce the formula for calculating the area of a circle; I want to learn how to calculate the area of a circle and so on. "After the learning objectives are clear, I found that the children in the two classes are very organized in their research. They all know what they are discussing and what problems they want to solve. I understood when I reported, I answered around the learning goals put forward before class, and I didn't talk nonsense. After the lecture tour, I realized from practice that the teaching goal is the starting point and the final destination of classroom teaching, and only by making clear the teaching goal can teachers better control the classroom; Only when students have clear learning objectives can they make progress and get twice the result with half the effort.
2. Teaching students in accordance with their aptitude in teaching form, and different classes and students adopt different teaching methods.
In class, every student is the object of our education. Different classes have different styles and characteristics. 10 1 The students in class were very quiet and didn't dare to speak at first. Therefore, when reviewing the area derivation of basic graphics I learned before, I first recalled the process of area derivation of various graphics. The children spoke very well, and I appreciated it very much. After they got to know me better, I discussed the active atmosphere in groups, and the effect was good. At the end, more students spoke and the answers were in place. The students in Class 98 are very active and quick-thinking. They are all scrambling to raise their hands, and I have a tacit understanding with the students. I left all my knowledge to them to solve, and used all the methods I could think of: discussion, self-study and guessing. Students can participate in the report, the formula derivation process is complete, and the exercises are not difficult to calculate. It should be said that Class 98 is the most dreamy class in the lecture tour.
In the whole teaching process, I played the leading role of teachers, highlighted students' dominant position, guided students to actively explore and study, obtained various methods to solve problems, and provided students with sufficient time, space and materials. Teaching is carried out around students' learning activities. Seize the precious opportunity to guide students to understand new methods and make new knowledge available at their fingertips. My biggest gain from the two classes is that my adaptability in teaching has improved, and different students have given me different experiences. Of course, I also found my own shortcomings: I still dare not let go and give the initiative to the students. Even if I let go, I will stick to it a little, which should be improved in my future work; Give students the necessary time to think after asking questions, and don't rush into it.
In the future teaching, I will deeply remember this lecture tour and continue to improve my teaching level.
Reflections on the teaching of "area of circle" 2 "area of circle" is taught on the basis that students master the meaning of area and the area calculation method of rectangular and square plane figures, understand the circle and can calculate the circumference of the circle. In the teaching design of this class, I pay special attention to following students' cognitive laws, paying attention to students' thinking process of acquiring knowledge, and learning and understanding mathematics from students' life experience and existing knowledge. The teaching in this section mainly emphasizes the following points:
1. Review the old knowledge to make necessary preparations for students to understand the meaning of the area of a circle and derive the formula for calculating the area of a circle by means of graphic transformation.
When reviewing, I first ask the students to recall the derivation method of the formula for calculating the area of plane graphics they have learned before, and reproduce the derivation process intuitively with the aid of teaching AIDS. In the process of reviewing old knowledge, students realize that the derivation of these plane graphic areas is to transform the graphics they want to learn into the graphics they have already learned by cutting, cutting and spelling, thus infiltrating the idea of transformation, and independently exploring "whether a circle can be transformed into a previously learned graphic to calculate its area" and guessing "how"
2. Guide students to actively participate in the process of knowledge formation.
This lesson focuses on the derivation of the formula for calculating the area of a circle. In teaching, the teacher, as a guide, only points out the direction of inquiry to the students and leaves the process of inquiry to the students. Students in small groups, through cooperative cutting and spelling, transform the circle into the learned figure (parallel four-sided row). After I show each group of cut and spelled figures one by one, combined with the demonstration of teaching AIDS, I guide students to observe that "the more copies are divided, the closer the figures are to a rectangle" and find the relationship between a circle and a rectangle, so as to deduce the calculation formula of the circle area according to the calculation formula of the rectangle area. In the whole deduction process, students always actively participate in learning and discussion, and experience the process of knowledge formation and the joy of success. This learning method not only helps students to understand and master the formula for calculating the area of a circle, but also cultivates their innovative consciousness, practical ability and exploration spirit. While mastering mathematics learning methods, students' concept of space has been further developed.
3. It embodies the close relationship between mathematics and life.
Mathematics comes from life, serves life, applies what you have learned, and solves practical problems in life is the ultimate goal of learning mathematics. In this class, students really feel that mathematics is around us, and mathematics is closely related to life. It is a happy thing to solve practical problems in life with what they have learned, thus establishing confidence in learning mathematics well.
4. Disadvantages.
It takes a lot of time to deduce and actually operate the formula of circular area, so the explanation of the derivation process is not thorough enough, and the students do not understand it deeply, so they do not have a good grasp of the formula. If we can study this point in time and give skillful guidance at that time, maybe students can understand it more thoroughly, then the whole class will be more exciting and substantial.
Reflections on the teaching of "circle area" 3 circle is the last plane figure in primary school. Students' learning has changed from rectangle to circle, from straight line to curve, both the learning content itself and the method of studying problems, which is a leap in learning.
Through the study of circle, students can understand the basic methods of learning curve graphics, and at the same time infiltrate the idea of migration and transformation. This not only expands students' knowledge, but also enters a new field in the concept of space. Therefore, through the study of circle-related knowledge, students can not only deepen their understanding of the surrounding things and stimulate their interest in learning mathematics, but also lay the foundation for learning cylinders and cones and drawing simple statistical charts in the future. So in this class, I designed this lesson plan:
First, review the basic knowledge and introduce new courses.
At the beginning of teaching, students should be guided to recall the area of plane figure and how the area formulas of parallelogram and triangle are derived, and the method of "reduction" should be infiltrated while reviewing. Can the circle be transformed into a plane figure they have learned before? How to deduce its area calculation formula? Introduce a new lesson "Area of a circle".
Second, guide the operation and deduce the formula for calculating the area of the circle.
First of all, understand the meaning of the area of a circle: guide students to recall what the area refers to. What does rectangular area mean? What is the area of a circle? By recalling the meaning of area, students can further deepen their understanding of the area of a circle and pave the way for the next exercise of "area of a circle". Next, guide the operation and deduce the formula for calculating the area of the circle: how to find the area of the circle? Students should think independently first. On the basis of students' own ideas, let students discuss their own ideas in groups, discuss the method of finding the area of a circle in communication, and transform the circle into a plane figure we have learned before by transformation method. Next, let the students take out their learning tools and practice by themselves, then leave enough time for students to think, let them work in groups, cut and paste and spell, and then transform the circle into a plane figure they have learned. Then guide the students to communicate and verify their own deduction ideas. Listen to the teacher and the students together, judge the derivation process of the formula of the circle area of the students, see if their own derivation method is scientific and reasonable, and let the students experience the learning process of operation and verification. This kind of orderly study improves students' practical ability and innovative consciousness, and then lets students practice to improve their own shortcomings, and tries to deduce the formula of circular area. In order to deepen the understanding of the formula of circular area, let the students show their derivation process on stage, which not only deepens the understanding of knowledge, but also exercises the children's language expression ability. Finally, the formula of circular area is deduced with teachers and students.
Third, consolidate practice and expand application.
In the consolidation exercise, I base myself on three levels: foundation, synthesis and expansion. First, the question type is basic for all students to consolidate the new knowledge I have just learned. On the basis of all students' mastery, I can comprehensively expand, so that I can face all students and take care of students with excellent learning. The practice effect is good.
Disadvantages:
1, classroom discipline is a bit chaotic, and students' discussion in the inquiry session is a bit intense, which directly leads to classroom discipline confusion.
2, the class time is not sure, the class bell rings, and the last few exercises are not handled.
3. The questions asked by the teacher are sometimes a little big, which makes the students don't know how to answer.
In the next teaching, we should correct our own shortcomings, improve our professional quality, and work hard again!
Teaching reflection on the area of a circle 4 This course adopts the form of courseware, which gives students a vivid, vivid and intuitive understanding, enlightens and clearly reveals the inherent laws of knowledge, and, together with students' practical operation and teachers' guidance and questions, enables students to cooperate and communicate in independent exploration, thus optimizing the teaching process.
First, let students participate in learning with multiple senses, form correct geometric concepts, master the characteristics and internal relations of graphics, stimulate students' interest and make them enjoy learning.
If the definition of the area of a circle is revealed, the concept of the area of a circle is basically established. Another example is to show the transformation process from a circle to an approximate rectangle by computer, to reveal the scientific beauty of the inherent laws of mathematical knowledge, and to fully embody the characteristics of composition beauty and dynamic beauty. It can stimulate students, enhance their curiosity, improve their desire to explore the mysteries of knowledge, help alleviate their audio-visual fatigue and improve their learning efficiency. Computer-aided teaching promotes the formation of students' good thinking quality and achieves the expected teaching purpose.
Second, introduce the mathematical virtual experiment into geometry teaching. By studying the area of the learning circle, highlight the main position of students' learning, and effectively cultivate students' innovative consciousness.
For example, when parallelogram, triangle and trapezoid are combined into rectangles and parallelograms with equal area and height after cutting and translation, the virtual experiment provided by the courseware makes the derivation process of their area formula completely presented to students. Students not only summarized the calculation method of area, but also realized the wonderful use of transformation thought in geometry learning. Moreover, students understand rigorous logical thinking training in the process of abstraction, generalization and inductive reasoning, which constitutes a method of learning geometry knowledge and produces a need, motivation and skill for self-trying, active exploration and willingness to discover. So it is logical to think that the formula for calculating the area of a circle can also be deduced in this way.
In teaching, we first show the process of dividing a circle into equal parts with animation, and then demonstrate the process of assembling a rectangle. After several similar experiments, the number of equal parts is increasing, and the assembled figure is getting closer to a rectangle. Students can draw that the area of the assembled rectangle is equal to the area of the circle, the width of the rectangle is equal to the radius of the circle, and the appearance is equal to half of the circumference of the circle, showing the derivation process of the circle area completely. Consolidation exercises should follow the principles of "from easy to deep", "from easy to difficult" and "step by step" to help students correctly master formulas and solve practical problems with knowledge on the basis of understanding concepts.
However, in the teaching process, due to the increase of teaching volume, students should be given more time to think and deduce the formula of circular area. The design of details should be carefully arranged. This is the place where teaching should be improved and the direction of future efforts.
Reflections on the teaching of "the area of a circle" Five circles are the last plane figures in primary schools. Students' understanding of straight lines and curves, both the learning materials themselves and the methods of studying problems, have changed, which is a leap in learning.
Through the study of circle, students can understand the basic methods of learning curve graphics, and at the same time penetrate the relationship between curve graphics and straight graphics. This not only expands students' knowledge, but also enters a new field from the perspective of spatial concept. Therefore, after learning the circle, it not only deepens students' understanding of the surrounding things, but also stimulates students' interest in learning mathematics, and also lays the foundation for learning cylinders and cones in the future.
First, I feel that the circumference and area of a circle are different.
At the beginning of this class, I asked students to compare the circumference and area of a circle, and then combined with the exploration method of recalling parallelogram, I guided students to find that "transformation" is a good way to explore new mathematical knowledge and solve mathematical problems, laying the foundation for the next step to explore the calculation method of the area of a circle.
Second, display learning tools to stimulate inquiry
Explore the area of a circle with the calculation method of parallelogram area derived above. Before exploring, I asked the students: How to calculate the area of a circle? The students are a little at a loss. In retrospect, I shouldn't ask how to calculate the area of a circle at first, but let the students guess what the area of a circle might be related to. When students guess that the area of a circle may be related to the radius of the circle, this introduction may be more helpful for students to answer my questions. Next, I asked the students to divide the small picture into several small sectors, from 8 equal parts, 16 equal parts to 32 equal parts. The students put these sectors together, from irregular shapes to approximate rectangles. Ask the students to find the perimeter and radius of the circle in this rectangle. Finally, the length of a rectangle is equal to half the circumference, and the width is the radius of the circle. Finally, the area formula of the circle is derived. (Unfortunately, the learning tools made by students themselves are inconvenient, time-consuming and irregular. If learning tools can be configured uniformly, it will be more convenient to operate. ) Students' thinking collides in communication, diverges in collision and improves in imagination. The initiative and creativity of thinking have been fully stimulated, and the ability to explore, analyze and solve problems has been improved. But it is worth reflecting that I have always held the idea of solving a knowledge point in a class, so in order to catch up with the time, I always pay more attention to the top students who raise their hands and pay little attention to the students with learning difficulties, leaving them with insufficient thinking time. This is what I should pay special attention to in classroom teaching in the future.
Third, practice in layers and experience the application value.
Combined with the examples in the textbook, I designed two levels of basic exercises and improvement exercises to test students' learning situation from two different levels. First, basic exercises consolidate the application of calculation formulas and emphasize the standardized writing format; Second, improve practice and collect practical information around you, so that the information learned in this lesson can be linked with life and used flexibly. In the setting of each exercise, there are different purposes, and I pay attention to the guiding points of each exercise. However, in the whole practice process, I failed to give full play to the leading role, reflect the students' dominant position, and guide students to consciously participate in the process of solving problems. In the future teaching, we should pay attention to students' participation and mastery of knowledge, promote students' active development and improve classroom teaching effect.
In this class, I always feel that the time to operate learning tools is very short and a little hasty. I just let the students operate carelessly, and more often, through the operation of my own teaching AIDS, I guide the students to observe, compare and analyze, and find out the relationship between the area, perimeter and radius of the circle and the area, length and width of the assembled approximate rectangle, so as to deduce the formula for calculating the area of the circle. Although students' thinking collides in communication, they always feel inadequate. In this kind of teaching in the future, students should be given enough thinking space and exploration time, so that the initiative and creativity of students' thinking can be fully stimulated and their ability to explore, analyze and solve the same problem can be fully improved. In addition, the detailed design should be carefully arranged.
Reflection on the Teaching of "Area of Circle" The sixth lesson "Area of Circle" is to let students actively participate in the whole process of knowledge formation to acquire knowledge, improve students' mathematical thinking ability of inductive reasoning, and infiltrate the view that extreme thinking is generally related to knowledge. Before class, I ask students to make a research report on this content. The purpose is: for excellent students, they should do their own research before class, while students with learning difficulties can't do their own research, and they will be impressed by reading and copying. Through this practice, we strive to make students acquire knowledge and cultivate innovative consciousness, inquiry ability and practical ability.
First, review old knowledge and infiltrate "transformation"
At the beginning of this lesson, let students recall the methods of exploring the area of parallelogram, triangle and trapezoid last semester, and guide students to find that "conversion" is a good way to explore new mathematical knowledge and solve mathematical problems, laying a foundation for exploring the area calculation method of circle in the future.
Second, make bold guesses and stimulate inquiry.
After emphasizing the importance of the area of a circle, I asked the students to guess what the area of a circle might be related to. When students guess that the area of a circle may be related to the radius of the circle, the design experiment verifies that the circle is drawn with the side length of the square as the radius, and the area of the circle is calculated by counting the squares, and the area of the circle is about several times that of the square. This content is not in the old textbook. Students' curiosity and thirst for knowledge are fully mobilized, and these are just "implanted" for their further exploration activities.
Third, demonstrate the operation and deepen the understanding.
When students pass the first operation activity, they know that the area of a circle is more than three times the square of the radius. Dialogue with the students: Just now, we learned that the area of a circle is more than three times the square of the radius, so how can we accurately calculate the area of a circle? Let's do an experiment. Every student has a circle in his hand, and now it is divided into 16 on average. What figure can you spell by yourself? Think about what this has to do with the circle. In this way, through students' operation of learning tools, abstract thinking is materialized into action image thinking, which allows students to participate in a variety of senses and conforms to students' cognitive level. Through observation, comparison and analysis, find out the relationship between the area, perimeter and radius of a circle and the area, length and width of an approximate rectangle, so that students can deduce the formula for calculating the area of a circle. In this way, students are guided to participate in the exploration of how to transform a circle into a rectangle (triangle or trapezoid) from support to release, from phenomenon to essence. Students' thinking collides in communication, diverges in collision and improves in imagination.
Disadvantages: the time given to students is still a little less. I am afraid that there is not enough class time, I dare not give students too much space, and I am afraid of losing my attention. Students' ability to speak in class needs to be improved, and some students can't answer the point. In the future, they will guide students more and cultivate their oral expression ability. These shortcomings will be gradually improved in the future teaching.