[Infiltration of Mathematical Culture in Symmetric Graphics Teaching] Axisymmetric Graphics Paper-cutting for Primary School Students

Mathematics curriculum standard points out that mathematics is a kind of human culture. Its content, ideas, methods and language are important components of modern civilization. If we can make full use of mathematical culture, let students accept its influence. Knowing its rich value will stimulate students' interest and thirst for knowledge in mathematics. Cultivating students' innovative spirit and practical ability has a positive role in promoting. More importantly, through the study of mathematical culture, students can be educated in personality and conduct. This paper takes the symmetrical graphics in the third experimental textbook of primary school mathematics published by People's Education Press as an example to talk about how to infiltrate mathematical culture in teaching.

The general idea is divided into four steps: talking to stimulate fun, playing with symmetry-experiencing characteristics and understanding symmetry-deepening experience and doing symmetry-enhancing understanding and appreciating symmetry.

Play symmetry. At the beginning of the class, the teacher said, children, today the teacher brought you a fairy tale. do you want to hear it ? Courseware demonstration: On a hot afternoon, a small butterfly dozed off on a leaf. At this moment, a little dragonfly flies around the little butterfly. The little butterfly woke up with a start and said angrily, "Little dragonfly, how can I rest when you fly around me!" " The dragonfly said, "How come you don't even know your family? I'm coming to play with you! " The little butterfly asked strangely, "I am a butterfly and you are a dragonfly." How can we be a family? " The little dragonfly smiled and said, "You don't know, do you? In the graphic kingdom, we are a family. There are many members in our family, and the leaves under you are also ours. " The little dragonfly is even stranger: "Is the leaf also a member of our family?" After the story was finished, the teacher asked the students: Why did Little Dragonfly say that he and Ye are a family in the graphic kingdom? Here we go. The teacher shows the students pictures of dragonflies, butterflies and leaves. Students can fold them up and draw a picture. Discover the * * * characteristics of graphics, and then, the teacher reveals the theme: symmetrical graphics. By introducing new lessons, students can understand the close relationship between symmetrical graphics and nature and understand its value.

Knowing the symmetry, the teacher guides the students to observe the left and right sides of the figure. And ask questions, what do you find? Tell your findings to the children in the group; What happens if the graph is folded in half? Then, guide the students to draw creases. Finally, the teacher reveals the characteristics of symmetrical figures: figures like dragonflies, butterflies and leaves completely overlap after being folded in half, so we say that they are all symmetrical figures, and this crease is called symmetry axis. When students know the characteristics of symmetrical figures, the teacher guides students to find symmetrical figures in their lives and inspires them to think: there are many symmetrical things, such as clothes we wear, scissors and glasses we wear. Are rectangles and squares symmetrical figures? How many axes of symmetry are there?

Symmetry is taught in three steps. First, the teacher cut out some symmetrical figures (planes, small trees, small fish, etc.). ). Only half exposed. Guide the students to guess what it is; The second is the discussion method. How can I cut out symmetrical figures? Students discuss in groups, and then exchange reports: first, fold the paper in half, cut out half of the graphics, and then open it to get symmetrical graphics; The third is for students to cut. Students have mastered the method of cutting symmetrical figures. Cut out the symmetrical figures you like, and the teacher will show the creative symmetrical figures on the blackboard for everyone to share.

Appreciating symmetry, symmetrical objects give people a symmetrical and balanced aesthetic feeling. Teachers can grasp the advantages of the beauty of symmetrical graphics, carefully design some activities to appreciate symmetrical graphics in life, and show them with courseware. Themes can be selected from natural animals and plants, ancient and modern buildings (Zhao Zhouqiao, Forbidden City, Olympic venues, etc.). ), daily necessities and so on. And end the new lesson with words of encouragement, praise and appreciation: in this lesson, we entered the world of symmetrical graphics, nature and human beings together. Butterflies and bees flying among the flowers, geese and pigeons flying in the sky, rainbows across the sky, and magnificent buildings created by working people in China. Vivid folk paper-cut window grilles, even each of us, each smiling face, don't you feel the power of symmetry? ...

The above-mentioned teaching activities have the following characteristics in infiltrating mathematical culture.

1, pay attention to highlight the cultural attributes of mathematics classroom. Mathematics has its rich cultural origins, but the boring and rote-learning teaching form has always been a stumbling block for students to learn mathematics. There are many reasons for this phenomenon: first, blindly pursuing the teaching of mathematical knowledge and the training of mathematical skills; The second is to dilute the cultural background contained in mathematics itself. Ignoring the essence of human exploration and discovery in the process of mathematics development and evolution and the inextricable connection between mathematics and life, the four-step design of the above teaching aims to tap the rich cultural resources (nature and human society) contained in mathematics, realize the harmonious unity of its scientific value and humanistic value, and cultivate students' innovative spirit of continuous exploration and discovery.

2. Pay attention to strengthening the cultural infiltration in mathematics activities, which is an important part of mathematics teaching. Carrying out colorful mathematics activities can give full play to students' initiative, let students be infected by culture in the learning process and experience the cultural taste of mathematics. Playing symmetry can make students question and stimulate their curiosity. Symmetry promotes students to master knowledge and increase their talents; Doing symmetry can develop students' hobbies and specialties and improve their learning ability; Appreciating symmetry can make students realize that symmetry is a kind of beauty, understand some characteristics of the motherland culture and broaden their knowledge.

3. Try to let students accept the influence of mathematical culture, collect as many materials as possible that can reflect the symmetrical beauty in teaching design, and attract students with the unique charm of mathematics, such as the symmetrical beauty in life, the symmetrical beauty in nature and the symmetrical beauty in ancient modern architecture. While students feel and appreciate the beauty of mathematics, their thinking flies out of the classroom and enters the distant world of mathematics, resulting in the impulse and desire to create the beauty of mathematics.

(Editor Zhong Yuhua)