This textbook includes the following contents: position, abdication and subtraction within 20, graphic assembly, digital understanding within 100, RMB understanding, addition and subtraction within 100 (1), understanding time, finding laws, and statistical and mathematical practice activities.

The key teaching contents of this textbook are: understanding numbers within 100, abdication subtraction within 20, and addition and subtraction within 100. On the basis that students have mastered numbers within 20, this textbook expands the range of knowing numbers to 100, so that students can initially understand the concept of numbers, learn to read and write numbers within 100, find out the composition and size of numbers within 100, and use these numbers to express and communicate, thus forming a preliminary digital consciousness. The addition and subtraction within 100 can be divided into oral calculation and written calculation. What appears in this textbook is the oral calculation part, that is, adding and subtracting one digit from two digits to calculate the whole ten digits. These oral calculations are widely used in daily life and are the basis for further study and calculation. So students should master it well. At the same time, the teaching materials are combined with computing teaching, and the content of applying the learned computing knowledge to solve problems is arranged, so that students can understand the practical application of the learned knowledge, learn to solve related computing problems in real life, and cultivate students' ability to solve problems with mathematics.