1. Understanding concepts: Mathematics is a basic subject, and learning mathematics must first understand concepts. Read the textbook carefully, understand the definition and nature of each concept, and master the basic theorems and formulas.

2. Do more exercises: Mathematics is a subject that needs to be practiced repeatedly. Through a lot of practice, you can improve your problem-solving ability and thinking ability. You can choose to do some problem sets or test papers, and insist on doing some topics every day to deepen your understanding and memory of knowledge points.

3. Pay attention to thinking methods: Math problem-solving needs flexible thinking methods, and you should learn to solve problems with different ideas and methods. You can cultivate your thinking ability and problem-solving ability by doing more comprehensive questions.

4. Take notes: In the process of learning mathematics, you can take notes and record important knowledge points and problem-solving methods. This can facilitate review and deepen the understanding and memory of knowledge.

5. Ask for help: If you have problems or don't understand, you can ask teachers, classmates or parents for help. They can give you some advice and guidance to help you solve the problem.

6. Make a study plan: make a reasonable study plan, arrange the time reasonably, and allocate the study time of each knowledge point. Learning according to the plan can improve the efficiency and effect of learning.

In short, the study of mathematics in Grade Three needs to understand concepts, do more exercises, pay attention to thinking methods, take notes, ask for help, and make a study plan. Through continuous efforts and persistence, I believe you will get good grades.