First, contact life, cultivate the concept of space
Students have been exposed to objects of various shapes since they were very young, and they have more early experience in the perception of shapes. These rich prototypes in real life are valuable resources for developing students' concept of space. When students learn geometry knowledge, they should first get in touch with the actual things they are familiar with in life. For example, in the teaching process of understanding objects and graphics, many familiar objects of various shapes in life are collected to guide students to learn. At the beginning of the class, I took out some objects, asked the students to name the objects, and guided them to name the geometry: for example, toothpaste box-cuboid, Rubik's cube-cube, teapot-cylinder, table tennis-sphere and so on. When the students were learning triangles, I took the triangle paper they usually played with and asked, "What shape is this?" "What other triangles have you seen?" At this time, students will immediately talk about their triangle, the red scarf around their necks, the roof truss of the house and so on. For another example, when we were studying "Understanding Rectangles and Squares", we had a conversation at the beginning of the class: "Students, every Monday, our school will hold a ceremony to ascend to heaven, and the five-star red flag will rise with the national anthem Ran Ran. Do you know what the red flag is? Look at the shape of handkerchiefs commonly used by children? " (Students answer the teacher's blackboard: rectangles and squares) The teacher then asks, "What other rectangular or square objects have you seen in your life?" . Through conversation, starting from the familiar situation and existing life experience of students, reveal the topic and initially perceive rectangles and squares. Teaching from the perspective of life is direct and effective.
Second, hands-on operation, establish the concept of space.
Piaget said: the formation of the concept of space is not like taking pictures. To establish the concept of space, there must be a hands-on process. It is an important way to cultivate students' spatial concept by comparing, analyzing and synthesizing with operations, so as to abstract the essence of things, gain an understanding of concepts, laws and relationships, and find out strategies to solve problems. In the teaching of Space and Graphics, the process of students' hands-on operation is actually the cooperative activity of students' multiple senses and the process of promoting the internalization of knowledge. Through operating activities, students can understand the knowledge about "space and graphics" more deeply and gradually form the concept of space. Therefore, in teaching, we should let students form a unified knowledge content and space by touching, comparing, measuring, drawing, folding, cutting and swinging from the perception of specific things, and establish geometric concepts to urge students to establish spatial concepts.
For example, when teaching the understanding of three-dimensional graphics, teachers can let students have a look and feel first, so as to further perceive the characteristics of cuboids, cubes, cylinders and spheres and cultivate students' operational ability. Then, guide students to operate freely, and let them experience the characteristics of cuboids, cubes, cylinders and spheres through comparison, rolling and building. Then inspire students to look for objects of various shapes from life. Finally, organize students to draw plane graphics with three-dimensional graphics, and let students experience the connection and difference between three-dimensional graphics and plane graphics. It can be seen that students organically combine thinking, watching, doing and speaking through practical operation. In mathematical thinking activities such as operation, observation and comparison, students' language expression ability, preliminary logical thinking ability and spatial concept are expressed and developed accordingly. This is not only helpful for students to establish the concept of space, but also to understand the practical application value of these shapes in real life.
Third, boldly imagine and develop the concept of space.
Einstein once said: "Imagination is more important than knowledge, because knowledge is limited, and imagination should summarize everything in the world." Imagination is the wing of thinking, which is often combined with activities such as observation, experiment and thinking. For example, from different angles, an object has different shapes. Students observe a panda doll from different angles, first draw what they see, then communicate with each other and guess who drew a picture and where he sat. In this way, students can observe, imagine, draw and compare objects or physical models in different positions, thus developing their spatial concepts. In teaching, students should also be encouraged to imagine boldly and let them fully display their inventions and creations.
Fourth, apply it in practice and deepen the concept of space.
Geometry is closely related to actual production and life. The teaching of basic geometry knowledge not only requires students to master physical characteristics and form correct concepts, but also requires students to deepen their understanding of knowledge, improve the spatial image of geometry and deepen the spatial concept on the basis of understanding the corresponding calculation formulas. For example, it takes six areas to calculate how many iron sheets are used to make a fuel tank, and five areas are needed to calculate the area around and at the top of the classroom, excluding the area of doors and windows. What is the shape of the pillar in front of the school administration building? How much aluminum does it need to be wrapped? Wait a minute. These are all practical applications of surface area calculation methods. For another example, after learning the volume of a cuboid, let students know that no matter where the cuboid is located, the size of the space occupied is the product of length, width and height, so the volume of oil in the oil tank is also the product of length, width and height. Through this series of practical activities, students' concept of space can be deepened.
In a word, the cultivation of the concept of primary school mathematics space is very important in primary school mathematics teaching. It is not only the basis for developing primary school students' spatial imagination, but also lays a good foundation for them to further systematically learn geometry knowledge and help them better understand the world. However, to cultivate students' concept of space, we must follow students' cognitive rules and combine theory with practice through actual observation, operation and bold imagination.