In the first grade, you can do the inverse of addition with subtraction and think with addition. You can also use the method of breaking ten, continuous subtraction (common method) and addition.

1. Do subtraction and want to add. Do the inverse of addition with subtraction and think with addition. For example, 12-8 and Xiang 8+( )= 12.

2. Violation of the Ten Laws. You can think of it this way: 10-7+3=6.

3. Continuous subtraction (common method). With continuous subtraction, you can think like this: 13-3-4=6, which means dividing 7 by 3 and 4.

4. Supplementary methods. You can also think like this: 13- 10+3=6.

5. Recite ten songs:

19 19 years of good friends,

Hand in hand,

3737 is so close,

Let's go together, four, four, six, six,

Make a pair of hands in half.

6. Interesting calculation:

Computing is a boring learning activity. In order to improve students' interest in calculation, some interesting calculation questions can be added to cultivate students' interest in calculation. Such as: find the law, swing the match with simple calculation to make the equation hold, and find a partner to compete.