I haven't understood mathematics since I was a freshman in high school. This is indeed an anxious thing, but it is also a common phenomenon. I'd like to offer some suggestions:

1, mental stability: You should know that this is a common phenomenon, not just caused by personal reasons, so you should not be anxious, because the more anxious you are, the more fearful you are, and the worse you are. If you want to learn well, one prerequisite is to listen carefully, even if it is specious, remind yourself to listen carefully.

2. Preview in advance: If the sports meeting lets you run and you don't know whether to run 100 meters or 1000 meters, then run quickly. What was the result? Can you run 1000 meter into1000 meter? Or take 1000m as1000 m to run? It will be a fiasco in the end. High school mathematics is abstract. If you don't preview in advance and attend class with questions, you may not be able to grasp the key points and difficulties, and you won't understand them soon.

3. If you don't understand, ask: If you don't understand in class, you can make it up after class, but you must make it in time. The teacher should ask after class, not accumulate more. It is more effective than asking excellent teachers and students, because there is not much difference in your understanding level, and teachers often rely on experience. Washing a pair of socks is not difficult, it takes a few minutes, but washing a pot of socks will make you worry and study. Don't let problems accumulate.

4. Understand the concept: Nowadays, teachers and students are too dependent on textbooks and ignore them. The textbook concentrates the efforts of experts and is the most authoritative information. Basic concepts in textbooks and questions after class are the most basic contents, but many students don't pay attention to them. Even the basic concepts and definitions are specious. If you do this and brush the questions, the result will be very serious. Once you figure this out, it won't happen once the topic changes. This is because there is something wrong with your basic knowledge.