You can consider buying a competition tutorial. Note that it is a book for beginners in the competition. If you don't think any junior high school books are suitable, buy a senior high school book to read. Although it will be a little harder, it will be good in the long run.

The middle school mathematics teaching assistant can choose the handbook of emphasis and difficulty, understand the examples of each section first, and then do the exercises; In the review stage, if it is only for the exam, it is recommended to do special exercises, that is, exercise books that separate each question type. Go to the bookstore and choose the answer first and explain it in detail. Finally, make a simulation test paper. There are many bookstores. Remember not to overdo it, or you will get tired easily. A thin one, about 12 sets, and you can buy it when it is finished.

If the self-study ability is not strong enough, it is recommended to have an excellent class, fully understand every question the teacher says, and be a master if you take the exam seriously.