The practical problem of "how many (how few) numbers a number is" in this lesson is learned on the basis of finding the sum of two numbers and the difference between some numbers and two numbers. Through the study of this lesson, it is not only conducive to further consolidating the addition and subtraction operations, but more importantly, it is conducive to enriching students' understanding of the meaning of addition and subtraction operations and expanding and improving their ability to solve practical problems by using the meaning of addition and subtraction operations.

The example designs flower arranging activities to guide students to compare two numbers in a row, and intuitively realize that "what is more than one number" can be calculated by addition, and "what is less than one number" can be calculated by subtraction. It is considered that the exercises in doing are close to the reality of students' life, which is of practical significance to help students experience the close relationship between mathematics and life in the process of solving problems, further develop students' problem-solving strategies and enhance their awareness of applying mathematics. This kind of textbook arrangement makes full use of students' own life experience, so that students can understand the basic quantitative relationship of related practical problems through intuitive operation, actively explore and master the solution, and avoid the difficulties that tedious analysis may bring to students.

Because the quantitative relationship of "how much is more (less) than a number" is abstract, and the calculation method is difficult to explore, it is necessary to create problem scenarios for students in teaching and guide them to observe, operate, discuss, communicate, reflect and summarize. Teachers should help students understand and master the quantitative relations and solutions of such problems while paying attention to stimulating and mobilizing students' enthusiasm for thinking. Teaching methods such as situational learning, demonstration operation and discussion can be adopted.

Teaching objectives:

1. Knowledge and skills: Make students contact the meaning of addition and subtraction with their own life experience, explore and understand the quantitative relationship in the simple practical question "What is the number more (less) than a number", and can use addition and subtraction to answer correctly.

2. Process and method: In the process of solving problems, students can further understand the meaning of addition and subtraction, cultivate their basic thinking ability, initially learn to reflect on the rationality of answers according to the meaning of questions, and constantly accumulate experience in solving simple practical problems.

3. Emotion, attitude and values: let students feel the close connection between mathematics and real life, experience the fun of cooperation and communication with classmates, and enhance their confidence in learning mathematics well.

Teaching focus:

Explore and understand the quantitative relationship in the practical question "What is the number more (less) than a number", and be able to answer correctly by adding and subtracting.

Teaching difficulties:

Explore and understand the quantitative relationship in the practical problem "What is the number more (less) than a number?"

Teaching preparation: self-made courseware, 33 pieces of magnetic flowers, and learning tools for students.

Teaching process:

First, create situations and introduce new lessons:

1. Create a situation: Xiaoying and Obana Xiaoping are good friends. This is a photo of the three of them. Look how proud and happy they are! They stand together, what can they compare? (height)

Students compare the heights of any two people.

2 follow-up: can you say that the temperature is high?

It is pointed out that there must be a comparison standard when comparing. Different comparison standards lead to different results.

Wen Wen is much higher than Hao. What can I say in turn?

Point out: These two sentences are different, but they have the same meaning.

[Comment: By taking photos and comparing heights, we introduce new lessons. On the one hand, we make full use of students' life experience, further experience the "comparative" mathematical thinking method, and pave the way for learning new knowledge. On the other hand, create a warm and harmonious atmosphere to make students feel close and actively participate in learning activities. ]