First, establish the concept of space
When teaching mathematical geometry in primary schools, we should make full use of what students are familiar with in their lives since childhood. For a long time, in primary school mathematics teaching, we often only pay attention to the knowledge in books, and stay away from life, which leads students to do only the questions in textbooks. Although the pupils are young, they have accumulated some life experiences and formed many mathematical representations. In teaching, students' existing life experience is closely linked with their real life, and familiar cases in students' life are used as mathematics materials, which makes students feel cordial and interesting and arouses their desire to learn mathematics. Space is a form of material existence, which is closely related to human existence and residence. Cultivating the initial concept of space is the basis of developing spatial imagination, and it is also one of the important tasks of mathematics teaching in primary schools. The concept of space is manifested in primary school mathematics: we can think of geometric figures from the shape of physical objects, imagine the shape of physical objects from geometric figures, and transform geometric bodies into their three views and expanded drawings; Can make three-dimensional models or draw graphics according to conditions; Can separate basic graphics from more complex graphics; Can describe the changes of physical objects or geometric figures; Can describe the positional relationship between objects in an appropriate way; Can use graphics to describe problems vividly; Think with intuition. In the actual learning activities, students often lack the concept of space, and the learning of geometry knowledge has become a difficult point for them to learn. We must pay attention to students' learning reality, proceed from students' reality, and effectively cultivate students' spatial concept. When students master the knowledge and methods of mathematics, they can apply them to real life and experience the fun of mathematics. For example, after students know the graphics, let them immediately observe the class to see which objects are the faces we learned today. The students found a lot at once. Later, in order to cultivate students' spatial observation, let students think about whether they have seen these figures at home or on the road. After the students imagined, they listed many objects. Students realize that we live in a world of shapes, and shapes can be seen everywhere around us.
Second, the formation of the concept of space.
Some teachers think that it is a waste of time to let students operate in class; Second, the order is too chaotic and difficult to regulate; Third, limited by learning tools. So if you can save it, you can simply use multimedia presentations instead of student operations. It should be noted here that students can't learn geometry knowledge without observation activities. In teaching, guide students to observe more, so that students can gradually obtain the representation of geometric shapes and form the concept of space. Let students observe the surface of some physical objects, or touch them with their hands, so that the images of specific things can be reflected in their minds and form representations, so that students can have a clear and correct understanding of concepts. Hands-on operation is the best way for students to form spatial representation and obtain spatial concept, which can help students accurately imagine geometric figures to form images of real space and figures, and can accurately describe the movement and change of physical objects or geometric figures. When teaching the area unit, students explore that the area unit is square by putting small disks, rectangles and squares. To compare the sizes of two graphs, it is necessary to unify the units. In the teaching of area units, in order to establish the appearance of 1 square decimeter and 1 square centimeter for students, the teacher asked students to find out which object around them has an area of 1 square decimeter and which part of the body has an area of 1 square centimeter or so. Connecting the representation in the mind with the practice in life, reproducing the area unit, and then constructing the concept of the area unit. Similarly, when constructing the concept of space with volume and unit of volume, we can touch, find and do it in the same way. When establishing the concept of "volume", we can experience it through experiments. Put a stone in a bottle full of water and the water will overflow. Guide students to observe the above experiments and draw the conclusion that objects occupy space. Let the students touch the eraser, pencil case and schoolbag, and ask which one takes up the most space? Thus, the concept of volume and space are obtained. When learning the surface area of three-dimensional graphics, students must do it by hand, such as designing and making rectangular boxes and making cylindrical cans. This requires students to have a clear representation of the development of various three-dimensional graphics. Therefore, in teaching, students should have a look, touch, compare, measure, think, draw a picture, fold it, cut it, put it on, and so on. Gradually establish the representation of graphics, so that students can further leave the image of spatial graphics in their minds, thus establishing and developing the concept of space.
Third, practical application.
Students are required to have strong comprehensive ability and practical operation ability, and students are trained to apply geometry knowledge to practice and solve practical problems by using measurement, calculation and geometric concepts and laws. Teachers should first train students to start with communication activities. In geometry teaching, students' operation and communication are essential. Teachers should provide materials to encourage and inspire students to use geometry knowledge to solve problems in life, so as to develop students' spatial concept. In teaching, students can take out a set of hard paper printed with right triangle, acute triangle and obtuse triangle with the same shape and size. First, cut out two right triangles and put them together at will to see what patterns they can make. Students can spell out half the area of rectangle, parallelogram and triangle, which makes students' understanding develop from concrete to abstract and from special to general. In fact, in the process of geometry learning, students' own creation plays a great role in developing the concept of space. For example, let students draw imaginary toys, castles, design garden plans and so on by using all kinds of geometric figures they have learned. In this process, students have to use various means, such as symmetry and translation. In such creative activities, students not only feel the beauty of geometry, but also consolidate their understanding of various graphics and develop their spatial imagination.
Four. Concluding remarks
Mathematics comes from and serves life. It is necessary for primary school students to understand the close relationship between mathematics and human society, understand the value of mathematics, enhance their confidence in understanding and applying mathematics, and learn to use mathematical thinking to observe and analyze the real society and solve problems in real life. Therefore, in the process of primary school mathematics teaching, it is necessary to enrich students' understanding of real space and graphics, establish a preliminary concept of space and develop thinking in images. Attaching importance to cultivating students' concept of space will not only help students better understand the world and solve problems in their daily life, but also lay a good foundation for further systematic study of geometry knowledge.