Add nursery rhymes in 20 minutes: 9 plus several, several minus 1, and write 1 in tens. Don't forget. (9+7,7-1 = 6, the result is 16)8 plus a few, minus two, and write1in tens. Don't forget. (8+7, 7-2=5, the result is 15)7 plus a few, minus three, and ten digits are written as 1. (7+7, 7-3=4, the result is 14)6. Add a few, subtract four, and write 1 in tens. (6+7,7-4 = 3, the result is 13)5. Add a few, subtract a few, and write 1 in tens. Don't forget. (5+7,7-5 = 2, the result is 12)

Benefits of mathematical formulas

Pupils are more emotional than rational in age, and their logical thinking ability is relatively poor, especially their spatial imagination. Therefore, for primary school students, mathematics is a boring and complicated subject. Therefore, self-made formulas play an important role in mathematics education, which can stimulate students' interest in learning mathematics and enable them to effectively remember mathematics knowledge.

For example, when learning a long cube, it is quite difficult for students to fold six faces into a cube. I came up with a formula to solve this problem. {If you don't see the field, go up step by step, and the words 14 1, will stir up the explosive charge, lower for a while and higher for a while, and 23 1, two words will stand in the middle and kneel down with their heads held high. It also stimulates students' interest in learning.

It is concluded that the self-made formula plays an important role in stimulating students' interest in learning primary school mathematics. Therefore, I often make up various formulas in teaching to fully stimulate students' interest in learning.