The object of mathematical abstraction is mainly the relationship between quantity and figure, and the abstract process is the process of giving up the physical background of load. In primary school, the abstraction of quantity and quantity relationship is mainly based on the relevant knowledge in "number and algebra", such as the abstraction of index, the abstraction of operational meaning and law, and the abstraction of quantity relationship. The abstraction of "number" has two core elements: one is "0-9" and the other is decimal notation system. The whole "number" system was established and developed on this basis. Therefore, the understanding of numbers within 5, 6- 10, 1 1-20 is the basis of digital concept teaching. Students should fully experience the abstract process of digital symbols and feel the concepts of decimal notation, carry and numbers.
The abstraction of digital operation runs through the whole primary school mathematics learning and is the most important learning content. The operation of numbers mainly includes integer operation → decimal operation → decimal operation. Each operation is closely related to mathematical abstraction in terms of operational significance and algorithm summary, especially algorithm summary and refinement. The purpose is to let students understand that number is the abstraction of quantity, realize the essential consistency of the concept of number, and form a sense of number and symbol; Understand the operation of numbers and the relationship between them, understand the essential consistency of digital operation, and form the operation ability and reasoning consciousness.