First, online teaching has obvious advantages: 1. Online teaching reshapes the collective atmosphere in the classroom. Network teaching, just a computer or a mobile phone, breaks the boundaries between time and space, and narrows the distance between teachers and students, so that everyone can study, discuss and learn from each other in the same class. Familiar with the friendly atmosphere, I resolved the loneliness of studying alone at home and gave me motivation and interest in learning. Especially in the early days of "anti-epidemic", such teaching activities dispelled the children's panic and loneliness and calmed people's hearts. Students have learned systematic knowledge about epidemic prevention in class and played an important role in real life. Online teaching and resource sharing have expanded the educational model. Online teaching makes the "famous teacher classroom" no longer far away, so that teachers and students have the opportunity to approach famous teachers, teachers learn superb teaching skills, and students get more and better learning guidance. Since the implementation of online teaching, our school has made full use of the resources provided by the national online education platform for primary and secondary schools, BBK education resource platform and learning power countries to carry out teaching. Teachers have widely collected the teaching videos of famous teachers in this discipline and shared them in class. Students sitting in front of the screen can appreciate the elegance of famous teachers from all over the country. Teachers with different styles, wonderful classes, and game activities brought by online classes all make students like learning content and are willing to participate in online classes. 3. Online teaching makes teaching more synchronous and helps to solve common problems in teaching. Offline teaching, it is difficult to grasp the teaching progress of each class in that year. After online teaching, more classes are broadcast simultaneously, and each class is taught synchronously. Once problems are found, they can be corrected in time, and good ideas and methods can also benefit the whole grade. Secondly, online teaching also has some disadvantages, which are embodied as follows: online teaching is difficult to restrain students' learning behavior. Since the beginning of online teaching, the most common question is whether the students are listening to the class, and the teacher can't know for the first time. The teacher asked questions in class and named a classmate to answer them. The nailing platform showed that the classmate was learning online, but there was no response to the teacher's continuous learning. This situation is the biggest problem that puzzles teachers. Network teaching does have a great influence on students with poor self-control In addition, in some families, parents can't accompany their children to class because of their busy work, and children are distracted or play online games, which leads to a significant decline in the performance of many students. It is difficult to correct homework in online teaching. For primary school students, face reform is an effective way to solve students' educational problems. In offline teaching, teachers can find problems in classroom teaching patrol and give immediate guidance, but online teaching can't achieve this effect. Even if students submit their homework, there are still many problems such as blurred photos, improper location and illegible photos. In addition, due to system reasons, mouse marking cannot be as smooth as handwriting, which is time-consuming and laborious, and affects marking efficiency. Online teaching, children are out of the supervision of teachers, which is not conducive to the growth of students. For primary school students, collective life is the cornerstone of their common growth. Children are separated from the collective and lack the guidance and supervision of teachers at home, which breeds some bad habits. For example, good writing habits are gone, and uploaded homework and handwriting are blurred and scrawled. The schedule of work and rest has been disrupted, and some students have been studying online in bed, using computers and mobile phones for a long time, which has also caused serious damage to children's eyesight.