Create specific situations, connect with things around you, help students know and understand symbols, help students understand symbols, expressions and relational meanings in actual problem situations as much as possible, and develop students' symbolic consciousness of solving practical problems. Practical background, exploration process and geometric explanation should be added to help students understand.

For example, in real life, signs in shops, red "X" signs in hospitals, traffic signs on expressways … all kinds of symbols can be seen everywhere. In this symbolic world, students' life experiences make them feel the practical significance of the existence of symbols. For example, they can immediately think of McDonald's when they see the exquisite "M" in front of the store. It can be said that in daily life, students have initially gained a sense of symbols, and they feel the simplicity, rigor and scientificity of symbols in their lives. This kind of symbolic consciousness has a positive role in promoting the formation of mathematical symbolic sense.

For another example, when teaching "Looking for the Law", the courseware shows that the lanterns on the roadside are arranged according to the law of purple, green, purple and green. Question: Can you find a way to show the regularity of this row of lanterns? Because lanterns are difficult to draw directly, it is easy for students to make use of the existing symbolic experience and think independently. Students can draw or write all kinds of symbols, full of personality. These symbols are just the existing symbol consciousness at work. Students are pleasantly surprised to find that they are also a researcher, explorer and discoverer!

Second, the combination of numbers and shapes creates a sense of symbols.

In the "number identification" unit of senior one, the textbook pays great attention to strengthening the understanding of the practical meaning of logarithm. After understanding 1-5, teach the understanding of logarithms and numbers, and let the students connect with their own life experiences and realize that a number can be used to represent the number of objects or the order in which objects are arranged. The textbook also attaches great importance to helping students establish the concept of number size and master the relationship between number size. In teaching, the example "=" > ""< provides a fairy tale scene "animal paradise", which abstracts the relationship between numbers from the comparison of different animals. The basic methods to compare the number of two kinds of objects are one-to-one correspondence and combination of numbers and shapes. Through one-to-one arrangement, students can clearly know their own numbers, thus establishing the concept of "as much as". On this basis, through the combination of numbers and shapes, they can abstract "4=4", know and understand the meaning of "=", and let students know that when the number of two objects is "as much", it can be expressed by "=". Then guide the students to compare the number of squirrels and bears in the sports meeting. Through one-on-one arrangement, let students know that there are more squirrels than bears, and bears are less than squirrels, thus establishing the concepts of "more" and "less", and abstracting "5>3" and "3" < learn to use ">" "< to express the relationship between the two numbers. It can be seen that the cultivation of symbol consciousness needs solid experience as the foundation. In teaching, students should be encouraged to accumulate experience in the process of communication and sharing, learn various symbolic ways, and allow personalized expression of symbols. Gradually realize the superiority of symbolizing practical problems with numbers and shapes, and feel the value of symbols in the process of understanding and solving problems.

Third, use it flexibly and strengthen the symbol consciousness.

Constructivism theory holds that teaching should not ignore learners' existing knowledge and experience and simply and forcibly "fill" knowledge from the outside, but should take students' original knowledge and experience as the growth point of new knowledge and increase new knowledge and experience. The formation of mathematical symbol consciousness should also follow this law.

For example, in the teaching of "Calculation of Triangle Area", guide students to deduce the area of triangle = bottom × height ÷2, and then write the letter expression: S=ah÷2 in time, which is convenient for memory and use. After applying this area formula to solve some simple practical problems, students can solve similar problems: it is known that the area of a triangle is 40 square centimeters and the base of the triangle is 16 centimeters, so as to find out the height of the triangle. This requires students to modify the area formula of the triangle: S=ah÷2→S×2=ah→S×2÷a=h, and thus the height of the triangle is 40×2÷ 16=5 (cm). In order to help students realize this symbolic operation, teachers can combine the derivation process of triangle area formula again, and realize that "S×2" means to calculate the area of a parallelogram with the same height as its base first, and "S×2÷a" means that the area of a parallelogram divided by its base equals the height, that is, the height of the triangle. The flexible use of symbols greatly enhances students' symbol consciousness.

Fourth, encourage innovation and enhance symbol awareness.

Symbols are used to express quantitative relations in specific situations. Like ordinary languages, basic letters must be introduced first. From the second learning period, it is an important step to express numbers with letters. From learning a specific number to expressing an approximate number with letters, students' understanding of symbols is gradually improved.

According to students' cognitive characteristics, help students straighten out the general symbolic relationship of mathematical concepts and laws, from experience to understanding and application, and then from understanding and application to innovation on demand, step by step, spiral upward, gradually establish symbolic consciousness, and realize the leap of students' thinking.