Numbers are the addition of 10 and the subtraction of 10.

Numbers are the addition of 10 and the subtraction of 10;

First, check the import.

1. Oral calculation: addition and subtraction within 9.

The teacher showed the verbal card and gave the password: the train goes forward and turns right. Students look at the formula and say the numbers directly.

2. Composition of10.

Students fill in the blanks independently and tell the answers.

3. Look at the formula in the picture.

Show:

Students first describe the meaning of the picture, and then list two addition formulas and two subtraction formulas.

Teacher: What can I do if I have mastered the composition of 10? Today we are going to learn the addition and subtraction of 10.

Second, guide exploration.

The addition and subtraction of 1. Self-study 10.

Combined with the exercise just now, students can list two addition formulas and two subtraction formulas according to a picture. Then can you show the composition of 10 with your school tools, and then list the corresponding addition formula and subtraction formula according to the diagram you put?

According to the example on page 56 of the book, please put it on the disc first, then say the meaning, and finally write the corresponding formula according to the meaning.

Students teach themselves, and teachers patrol individual guidance.

2. Exchange self-study results.

Who will report how you play, say and write?

Please come to the front to demonstrate and report, and the teacher will write on the blackboard.

3. Summarize the algorithm.

If there are no pictures in these groups of questions just now, how to calculate them (add according to the composition of numbers and subtract according to the decomposition of numbers). ) What else can I do? (calculated by counting. Want to add and subtract)

4. Calculate □□

Can you calculate? Tell me what you think.

5. Knowledge expansion.

Addition and subtraction of 10, what else do you know besides these formulas? ( )

Praise the students who said the above formula.