With the deepening of curriculum reform, many teachers feel that there is an obvious two-level differentiation in primary school students' learning, the time of differentiation is advanced and the distance of differentiation is widened. Teachers generally reflect that after the curriculum reform, some students' ability is better, and some students are more difficult to learn. Especially after we used the textbooks of Jiangsu Education Edition and People's Education Edition, we obviously felt that the phenomenon of differentiation was more serious in the third grade. Although there are always differences in students' learning, the time of differentiation has advanced and the distance of differentiation has increased, which has brought great inconvenience to our teachers' teaching. In class, good students often don't have enough to eat, but students with learning difficulties can't eat. It is difficult to improve the overall class achievement gap, so polarization is a realistic problem that we urgently need to solve. There should be many reasons for the polarization of primary school students, including intellectual factors, but the proportion of polarization caused by non-intellectual factors is high. In order to narrow the gap, as teachers, we should pay attention to the following points: First, teachers should not teach new textbooks to death. For new textbooks, teachers should try to understand thoroughly, understand the characteristics and intentions of the new textbooks, grasp the context of the new textbooks, dive deep and jump high, so as to use the textbooks flexibly and teach them vividly. Moreover, they should pay attention to the connection between various knowledge points. The second point is that teachers should always pay attention to the disadvantaged groups in the class, especially those children who are easily distracted in class, encourage and remind them, stimulate their interest in learning, mobilize their enthusiasm for actively participating in classroom learning, let them experience the happiness of success, and gradually form good study habits, so that every student can get real development. In addition, teachers should constantly improve their classroom teaching level. Pay attention to the details of classroom teaching and strive to improve the ability of classroom regulation. For example, in classroom practice, pay attention to feedback information effectively, pay attention to students who make mistakes, help them analyze the causes of mistakes, and prevent them from falling behind at the starting point. Third, teachers should recognize and treat the differences between students well. Ten fingers are also long and short, so we can't take the ratio of length to length, which makes students feel that no matter how I jump, I can't reach the peach, so I lose confidence in learning. It's getting worse. The requirements are hierarchical. For those students who are already at the bottom, we must be strict with the most basic problems, such as basic calculations, concepts, simple application problems and so on. They must lay a solid foundation to prevent backwardness. Problems that are too difficult to solve can be lenient to them. Effectively improve the effectiveness of classroom teaching. Fourth, give play to the role of collective learning. Group cooperative learning can help students learn from each other's strong points and narrow the gap between students at both ends, and both sides can benefit, especially the underachievers. In the traditional teaching with teachers as the main body, students with poor foundation can't keep up, but they are afraid to ask and have no chance to ask. The problem can't be solved, and the gap is getting bigger and bigger as time goes by. They may ask questions in small groups they are familiar with, because the atmosphere of group discussion and learning helps to ease their inner tension and make them dare to ask questions, and the collective wisdom of the group helps to solve problems. At the same time, it is also an exercise for students who help. Both sides will have the joy of successful cooperation.