There are usually hundreds of tables in the textbooks of the first grade of primary school (learning factors and multiples, prime numbers (prime numbers) and composite numbers are also useful in the fifth grade), which is intended to let students know more clearly the arrangement order of numbers within 100 after they know the numbers within 100, which not only consolidates the numerical order of 100, but also can be used in tables.

A hundred meters is helpful to discover the law of numbers within 100. There are rules to follow in both directions. For example, any number on a hundred meters is 9 different from its neighbor in the upper right corner and the lower left corner. For another example, as shown in the following figure, the sum of left oblique numbers, ten digits plus one digit shows the laws of 2, 4, 6, 8, 10. It can not only improve children's interest in learning mathematics, but also broaden their thinking.

Every line, every column and every diagonal number on the 100-meter line has basic rules in it. After a little thinking, you can understand why there are different laws. Because the distance and position of each number are different in essence, it represents different values of addition, subtraction, multiplication and division, so it presents an interesting law.

Precautions:

1, through observation, speculation, verification and conversation with people to understand the hundred tables and explore the arrangement law of the hundred tables.

2. Write numbers with the description of rows and columns in a hundred tables. I feel that the position of a number can be determined by (the number of rows and columns).

3. Explore all kinds of interesting laws on hundreds of tables.

4. Combining the teaching atmosphere of situations and practical activities, analyze the information in hundreds of tables, cultivate students' observation and analysis ability, and gradually develop students' mathematical thinking.