Compass is a tool for drawing and measuring circles, which plays an important role in students' geometry learning. Then, let's discuss the role of compasses in students' study and the timing of their use. Generally speaking, compasses are generally introduced and used in junior high schools. In China's school education system, students usually start to contact and use compasses in the seventh or eighth grade mathematics curriculum. This period is the time when students begin to study systematically.

The stage of learning geometry knowledge, and compasses, as one of the important tools in geometry, will become a part of learning. In junior high school, students have mastered some basic mathematical knowledge, such as straight line, angle, triangle, quadrilateral and other concepts.

When students have a certain understanding of these basic concepts, the teacher will gradually guide them to learn pi, pi and other related contents, and begin to use compasses for practical operation.

Using compasses requires some skills and precautions. Students need to learn how to hold compasses correctly, determine the center of the circle, draw an arc and so on. Teachers will guide and demonstrate students and help them use compasses correctly, practice and practice again.

By using compasses, students can understand the nature and characteristics of circles more intuitively, learn how to draw circles and arcs, and deepen their understanding of geometric figures.

At the same time, the use of compasses also cultivates students' observation, patience and practical ability, and promotes students' interest in mathematics and enthusiasm for learning.

It can be seen that compasses, as an indispensable tool for learning geometry, play an important role in students' mathematics learning, which provides students with an intuitive and practical learning environment and helps them better understand and master geometry knowledge. Therefore, the seventh or eighth grade is the time for students to start learning and using compasses, and it is also an important node for them to gradually deepen their mathematics learning.