1. Preparation materials: cardboard, scissors, pencils, compasses, rulers, thumbtacks, fan-shaped templates, rotatable cardboard trays, and silk ropes.

2. Making the tray body: draw a circle with a diameter of 10cm on the cardboard with a compass, and cut it out to become the tray body.

3. Making dial: draw a dial on the cardboard with a fan-shaped template, the size of which is the same as that of the tray body, and connect the dial and the tray body with pushpins.

Mathematics is introduced as follows:

Mathematics is a universal means for human beings to strictly describe and deduce the abstract structure and mode of things, and can be applied to any problem in the real world. All mathematical objects are artificially defined in essence. In this sense, mathematics belongs to formal science, not natural science. Different mathematicians and philosophers have a series of views on the exact scope and definition of mathematics.

The development of mathematics is introduced as follows:

Algebra can be said to be the most widely accepted "mathematics". It can be said that the first mathematics he came into contact with was algebra since everyone began to learn to count when he was a child. Mathematics is a subject that studies numbers, and algebra is also one of the most important parts of mathematics. Geometry is the earliest branch of mathematics studied by people.

Until the Renaissance in16th century, Descartes founded analytic geometry, which linked algebra and geometry which were completely separated at that time. From then on, we can finally prove the theorem of geometry through calculation; At the same time, abstract algebraic equations and trigonometric functions can also be graphically represented. Then more subtle calculus was developed.

The definition of mathematics is introduced as follows:

Aristotle defined mathematics as "quantitative mathematics", which lasted until18th century. /kloc-since the 0/9th century, mathematical research has become more and more rigorous, and it has begun to involve abstract topics such as group theory and projection geometry that have no clear relationship with quantity and measurement. Mathematicians and philosophers have begun to put forward various new definitions.

Some of these definitions emphasize the deductive nature of a lot of mathematics, some emphasize its abstraction, and some emphasize some themes in mathematics. Even among professionals, the definition of mathematics has not been reached. Whether mathematics is an art or a science has not even been decided.