The new curriculum standard of primary school mathematics regards cultivating students' spatial concept as one of its core tasks, so it is necessary to explore the strategy of cultivating students' spatial concept under the concept of new curriculum reform. This paper will discuss the premise, how to cultivate, how to develop, how to accumulate and then cultivate spatial imagination with examples. Combined with students' life experience, with the help of physical objects and multimedia applications, students' concept of space can be effectively cultivated.

Keywords: spatial concept, perception and imagination

Mathematics is a science that studies quantitative relations and spatial forms in the real world. Space is inseparable from our life. Cultivating students' concept of space is an important teaching content of primary school mathematics, which includes "number" and "shape", in which "shape" refers to the preliminary knowledge of geometry and is one of the main contents of primary school mathematics. The new curriculum standard of primary school mathematics regards cultivating students' preliminary spatial concept 1 as one of the core tasks of teaching. However, this part of knowledge has become the weakest link in students' learning process, and it is also the most headache for teachers in teaching. Pupils' spatial awareness is often formed in the process of learning the initial knowledge of geometry, so only by putting the cultivation of students' spatial concept into practice can students' spatial concept be truly developed. According to the characteristics of primary school students' thinking development, combined with some teaching contents of "Space and Graphics", this paper talks about my own superficial ideas.

Spatial concept: it is a representation of the shape, size and position relationship of objects formed on the basis of spatial perception, and it is formed on the basis of comprehensive perception of similar things.

First, use life experience to cultivate students' concept of space. (1) Break through the simple understanding and establish the initial space consciousness. Pupils have been in a curious desire for external things since childhood, and they have been exposed to various graphics to understand things since childhood, so that they gradually have a preliminary perception of three-dimensional graphics and plane graphics, and form shallow representations of these graphics in their minds. 2. The formation of these representations is the germination of the concept of space. Everything in life is a valuable resource for primary education, and learning geometry knowledge is based on seeing pictures and touching objects. Such as cups, televisions, doors and windows, books, cartons, houses, streets, etc. , let them know about the line, surface, body, angle of the preliminary knowledge; "The Sun Rises in the East" knows the direction; Translation of driving, flag raising and flag lowering; Observe the rotation phenomenon from the rotation of windmills, ferris wheels and propellers. Teachers should teach according to the thinking characteristics of students in this period, closely link teaching with life, and form their initial spatial knowledge with rich realistic prototypes. Starting from simple and interesting, grasping the characteristics, let primary school students form a cognitive process from shallow to deep. The initial formation of spatial consciousness helps them understand things. Through guidance, let them break through simple understanding, have shallow abstract understanding ability, cultivate their perception of life, and let mathematics come from life.

(2) Abstraction of physical objects into plane graphics to cultivate students' spatial imagination. "Teaching research shows that the thinking of students in the lower grades of primary school is in the stage of intuitive image thinking, and the thinking characteristics mainly rely on the concrete image and representation of things to carry out thinking activities." Through the accumulation of knowledge and experience, the thinking of primary school students gradually changes from an intuitive image to an abstract logical image: an image that appears in an individual's mind when something is not in sight.

The development of thinking and the cultivation of spatial sense are also the training stage of abstract thinking, so "thinking" should be the main body in teaching, giving students broad space for thinking development. In recent years, teaching is no longer a cramming teaching method, but focuses on students' autonomy, ability training and thinking development. Teachers are no longer simply "teaching" and students are no longer simply "learning". After contacting primary school students, we will find that their imagination is very rich, and imagination is a manifestation of thinking in images, and these rich spatial imaginations can further develop students' spatial concepts. Many inventions are made by designers who first have imagination, then draw design drawings according to their own imagination, then make physical models, and modify the design countless times, until the final perfect shape, only then can we use the physical objects. In these processes, physical objects are abstracted as plane figures in the mind, and the concept of space plays a vital role here. Without a good concept of space, it is impossible. The concept of space also plays an important role in the development of students. If role-playing can be carried out in the classroom, teachers should set the story background, provide roles, let students enter it, freely play, fully imagine, let students participate in it and study hard. Through role-playing activities, students have the opportunity to practice different people's feelings, attitudes, values and problem-solving strategies. You can also arrange open homework after class, such as designing flower beds under certain conditions. Through measuring, conceiving, making design drawings, comparing various design schemes and other activities, students' thinking gradually developed into abstract thinking, expanding their thinking space.

Second, deepen students' understanding of geometric concepts and deepen the concept of space.

(A) the use of CAI to cultivate and develop students' concept of space. Nowadays, computer multimedia teaching methods have been brought into the classroom. Through CAI, students can present familiar objects, let them know the characteristics of objects from perception, and then understand geometric concepts. Make the teaching content vivid, dynamic and intuitive, improve the teaching efficiency, and cultivate students' spatial concept well. Geometric concept is obtained by people's highly abstracting a large number of spatial forms in the real world in their long-term life and production practice, so the cultivation of spatial concept is the condition for better understanding geometric concept. The formation of space concept is inseparable from geometric concept, and the establishment of geometric concept is based on the appearance of body. It can be seen that the understanding of geometric concepts is closely related to the establishment of spatial concepts. For example, when teaching the perimeter of a rectangle, teachers can use multimedia CAI to make courseware, so that the learning content can be vividly presented and students' interest in learning can be stimulated. On the basis of students' basic understanding of rectangles, further guide students to learn, collect a large number of life materials in their lives and present them to students with courseware, as shown in figure 1. Let the students know these objects, observe their characteristics, make them realize that they are all figures surrounded by some edges, and then think that they are all composed of several edges. Figure 1 Finally, it is concluded that the sum of all the edges around a graph is the perimeter of the graph (that is, the concept of perimeter). After students understand the concept, take a rectangular object as an example for dynamic demonstration, as shown in Figure 2. Expand the four sides of a closed object one by one, pull it into a straight line, and then restore it. Through this demonstration process, students can form concrete and vivid images in their minds and deepen their understanding of the concept of perimeter. The high abstraction of geometric concepts makes it difficult for students to understand and becomes a difficult point in primary school teaching. Using multimedia can overcome this difficulty and cultivate students' spatial concept.

(2) Consolidate students' spatial concept through various perceptual activities. Most of primary school students' graphic knowledge is obtained from hands-on operation. Psychological research has proved that many senses such as vision, touch and hearing participate in the operation of geometric materials, which is conducive to the consolidation of spatial concepts. Experience and understanding in the process of hands-on can further develop the original consciousness. In the teaching of cuboid volume, the textbook does not give the definition of cuboid, but points out the shape of the object by observing the graphics. Therefore, teachers can use the most common paper boxes in life as teaching AIDS, let students observe the composition of the paper boxes first, and then let students start to disassemble the paper boxes, unfold them into planes, and draw opposite faces with the same color for comparison, as shown in Figure 3. Make the image of specific things fully reflected in the mind, and deepen the understanding that "six faces are long (positive) squares, and the opposite big pictures 2 and 5 can make students' thinking fully divergent, which is conducive to strengthening thinking training and improving thinking ability". Therefore, students can improve the accumulation level of spatial concepts by paying attention to training divergent thinking while flexibly using what they have learned. Fourth, the possible problems in cultivating students' spatial concept. In the teaching process of cultivating students' space, teachers ignore the limitations of students' thinking development, which leads to students' misunderstanding of space to some extent. In the process of teaching, I found some shortcomings of students in this respect. For example, when learning verticality and intersection, students can easily see the vertical phenomenon by observing the schematic diagram of two mutually perpendicular straight lines. If the direction is rotated, students will think that it is only intersecting rather than vertical after observing it again; In the comparison of learning angles, if the two lines of one angle are extended, and students compare again, some students will think that the changed angle (∠2) is larger; When learning a long (square) cube, it is easier for students to accept what it is if it is explained by physical objects, but it is difficult for students to accept it if it is explained by plane three-dimensional graphics. They will think that two of the three planes they can see are parallelograms, and not all the angles are right angles. As shown in Figure 6, these phenomena are students' wrong spatial cognition in senses such as vision. Figure 6 shows that their sense of space is only based on a certain degree. If the content they are exposed to exceeds this degree, they will have a wrong understanding. Students' thinking has not been completely abstracted from the appearance, and things and graphics have not been well connected in their minds. Therefore, when teaching in this field, teachers should jump out of the old teaching methods, adopt various teaching methods and means, explain knowledge from various angles from the standpoint of students, guide students to actively participate in teaching with various senses, and eliminate students' illusion about the concept of space. According to students' cognitive rules, eliminate their psychological interference in learning. Strengthen students' learning ability from perception to representation, and then from representation to abstract concepts, and cultivate good spatial concepts. To sum up, the cultivation of spatial concept is a step-by-step process, which must be gradually formed, deepened, developed and consolidated on the basis of mastering the basic knowledge of geometric shapes, combining with various perceptual activities and applying preliminary geometric knowledge in simple practical activities. In the initial stage of primary school students' development, it is very necessary to cultivate students' spatial concept seriously. A good concept of space will not only help students better understand the world around them, improve their reasoning and thinking ability, but also gradually form their spatial imagination ability, thus strengthening their memory of what they have learned, and laying a good foundation for their future study and development, so that they can be fully and comprehensively developed.