Students will inevitably make some mistakes in the process of learning mathematics. However, in traditional teaching, teachers are afraid that they have not made it clear, that students don't know this or that, and that students make mistakes of one kind or another. So the teacher lectures more and more carefully, analyzing everything, and pursuing knowledge in one step. In fact, as a math teacher, don't be afraid of students making mistakes. We should encourage students to explore and analyze problems themselves and allow them to make mistakes. Sometimes mistakes are beneficial to teaching and students' better mastery of mathematics knowledge. Mathematics teachers should be good at turning "mistakes" into valuables, correctly treating students' mistakes in the process of learning mathematics and making rational use of these "mistakes" resources. There is a story in the music industry. Seiji Ozawa, a world-famous conductor, interrupted his command three times in a row when he took part in a world competition because he decided that there was "mistake" in the score. In fact, this is a "trap" deliberately set by the judges. In fact, the bold denial of this "trap" is verifying Seiji Ozawa's real strength as a music conductor. Teachers should also be good at setting some such traps properly, and even induce students to make mistakes and let them fall for it. When they fall into the trap and are still intoxicated with the joy of success, they should point out their mistakes. Through right and wrong analysis, let them wake up from their mistakes and learn from them, and often get the effect of "learning from the past". Because of the great emotional contrast, students are naturally impressed by the obvious contrast between right and wrong. When Madame Curie was in primary school, the teacher once told her classmates that if you put a pebble in a glass full of water, the water would overflow, but if you put a goldfish, the water would not overflow. After school, Madame Curie felt that the teacher's conclusion was doubtful, so she did the experiment herself, and the glass of water overflowed. A teacher's deliberate "mistake" cultivated Madame Curie's excellent learning quality of being good at questioning! In fact, the process of students acquiring mathematical knowledge is actually a process of continuous exploration. Through the teacher's initiative to present mistakes, students' psychology has ripples, which aroused students' curiosity. Teachers' intentional "mistakes" in the classroom can effectively adjust the teaching atmosphere and make the unremarkable classroom more attractive. Teachers' intentional mistakes lead students to fall into a contradictory and confused situation, which makes students doubt their own cognition and reflect on themselves, learn from their mistakes, find out the reasons from their failures, and let students open their wisdom and enter the temple of knowledge by correcting their mistakes. Franklin has a famous saying: "When a baby is misplaced, convenience becomes a waste". With the implementation of the new curriculum with the concept of "all for the development of students", it is necessary for us to rethink and locate the mistakes in students' learning from a brand-new perspective, put the "mistakes" in a correct position, and let the baby shine. Teachers should let students try and make mistakes in practice, and then look for a "panacea" to cure "mistakes" after having the wrong experience, so as to get twice the result with half the effort.