1 use form to promote thinking. In the teaching of digital cognition, understanding and using numbers is an active, conscious or automatic attitude and consciousness, and it is a direct, rapid, correct and sensitive feeling ability for mathematical objects and materials. "Mathematics Curriculum Standard" points out: "The sense of number is mainly manifested in understanding the meaning of number; Numbers can be expressed in many ways. " For example, when teaching the understanding of 10, I asked my children to observe the pictures carefully. What do you know from the picture? Let the students count on the stage with their counting experience. Students understand that both 10 people and 10 pigeons can be represented by the number 10. Then let the students operate with a stick and know that a bundle is 1 10, so 10 1 is ten. Then I asked the students to find out which objects in life can be represented by the number 10. Finally, let the "10" baby join the digital queue. The numbers from 0 to 9 have been lined up in the order from small to large (showing the ruler map). /kloc-where should the 0/0 baby line up? Please ask the counter for help. How much should I add (let students intuitively feel that 9 is greater than 8, 1)? What's nine plus one? 10 How much is it if one is removed (make students feel that 10 is more than 9, 1)? Where should 10 be ranked? Go back to the ruler chart and ask the students to guess what is behind 9. Please read the numbers 0 ~ 10 from small to large and from large to small respectively. In the above teaching, I skillfully infiltrated the thinking method of combining numbers and shapes, so that students can further strengthen their sense of numbers and deepen their understanding of logarithmic meaning in their perception and experience of specific quantities.
In concept teaching, it is an important part of knowledge teaching to strengthen experimental operation and infiltrate the thinking method of combining numbers and shapes. In concept teaching, it is not enough to clarify its practical significance, but also to comprehensively analyze the concept from the aspects of the whole, essence and internal relations of things and highlight its essential attributes. However, its abstraction and dullness make the teaching effect unsatisfactory and students have difficulty in learning. With the help of intuitive graphics, strengthen the experimental operation, make the concept teaching interesting and vivid, thus helping students understand the formation process of concepts in a relaxed and happy learning atmosphere.
For example, in the teaching of "Understanding Volume", I infiltrated the thinking method of combining numbers and shapes through three steps, so that students can intuitively understand concepts with the help of shapes: 2. 1 Through experiments, students can realize that objects occupy space. The teacher showed two identical cups, one on the left was filled with water, and the other on the right was filled with citrus fruits. Please guess what will happen if the water in the left cup is poured into the right cup? Students guess and verify whether the guess is correct through experiments. Students understand the operation of pouring water: it turns out that two cups contain the same amount of water. Now, if you put in a citrus fruit, some space in the cup is occupied by citrus fruit, so the space for holding water becomes smaller. Let students realize that objects occupy a certain space.
2.2 Through experiments, let students realize that the space occupied by objects is large and small. Show two identical glasses: one filled with citrus fruits and the other filled with grapes. If you pour water into these two cups, which one will hold more water? Students guess and test the conjecture again: two cups can hold the same amount of water, and oranges occupy more space, so there is less water in the corresponding cups; Grapes occupy less space, so there is more water in the corresponding cup.
2.3 reveal the meaning of the volume. Show me three fruits of different sizes. Which of these three fruits takes up more space? Put them in the same cup and fill them with water. Which cup takes up more space? The students' experimental operation shows that an object occupies space. The bigger an object is, the more space it occupies. On the contrary, the smaller the object, the smaller the space it occupies. We call the space occupied by an object the volume of the object. Students use life examples to compare the sizes of two objects and know the volume. Through three-stage teaching, the experimental operation is strengthened and the thinking method of combining numbers and shapes is infiltrated. Students can not only intuitively understand concepts by borrowing tables, but also apply concepts.
Look at the imagination of form, and combine the teaching of "quantity measurement" with the thinking method of combining number and shape to help students establish qualitative concepts. The main research objects of mathematics are number and shape. But in real life, number and shape, quantity and measurement are always closely linked, and learning mathematics must involve quantity and measurement. How to combine numbers and shapes in quantity and measurement?
For example, the teaching of "understanding of kilograms": ① understanding scales and scales. Observe the scale surface as seen from the scale surface. ② Establish the quality concept of 1 kg. A. Take a look and experience the weight of one kilogram. Weigh 2 bags of salt in groups and observe that the weight of 2 bags of salt is 1 kg. B guess again and experience the weight of 1 kg. First guess how many apples, oranges and peaches there are, and the weight is 1 kg, and finally weigh them. How many such fruits are there? C. compare and deepen the understanding of one kilogram. The teacher showed a 2 kg rice, let several students carry it, talk about their feelings, and guess how many kilograms it weighs. Through comparison, the experience of 1 kg is further deepened.
It is abstract for students to establish the concept of "kilogram" as a unit of measurement, and it is easy for students to establish and apply the representation of "kilogram" by infiltrating the thinking method of combining numbers and shapes.
4 Look at numbers and shapes. In problem-solving teaching, the combination of numbers and shapes is infiltrated to make the problem-solving process concrete and clear. Mathematician Hua once said: "For a long time, people have a boring, tasteless and mysterious impression of mathematics.