Pencil case, also known as pencil case, pen case, stationery box, is one of the essential items for students' study. It is a container used to store pencils, pens, erasers, rulers and other stationery. Pencil cases can be of various shapes, sizes, and materials, including plastic, metal, cloth, and leather. The origin of pencil cases can be traced back to China in the 1st century BC. At that time, bamboo tubes were used to store pencils and ink. By the 14th century A.D., Europeans began to use paper, and they also began to use cartridges to store pen and ink. The materials used for pencil cases changed with the times. Initially, most pencil cases were made of wood or metal. Later, with the development of the plastic industry, pencil cases also started to be made of plastic. Plastic pencil cases have the advantages of being lightweight, durable and inexpensive, so they soon became the mainstream material for pencil cases.
 The shape of pencil cases also changed with the times. Initially, most pencil cases were rectangular or square. Later, with the improvement of people's aesthetic level, the shape of the pencil case also became more diversified, and there appeared a variety of shapes such as round, oval, heart-shaped pencil cases. The colors of pencil cases are also very rich, which can meet the preferences of different students. Common pencil case colors are red, blue, green, yellow, black and so on. Pencil case is not only a necessary it