Quantity refers to the nature that objects or phenomena in the objective world can be qualitatively distinguished or measured, and can generally be divided into continuous quantity and discontinuous quantity. Discontinuity, also called separation quantity, is a quantity that represents the number of elements in an object; Continuous quantity, also called correlation quantity, is a quantity that represents the properties of an object, such as length, area, volume, etc.

Comparison refers to the establishment of the relationship between two or two groups of objects according to a certain attribute, which is one of the common methods of children's mathematics learning and the basic process of individual thinking. For preschool children, learning to compare correctly is one of the important values they should pursue in mathematics learning.

The comparison of quantity includes the comparison of discontinuous quantity and continuous quantity. Among them, discontinuous comparison refers to the comparison of the number of two groups of elements, which is generally carried out one-to-one by overlapping, juxtaposition and connection.

Because quantity comparison is usually placed in the category of "number concept", this paper will not focus on it. The comparison of continuous quantities refers to the comparison of the properties of objects-size, length, thickness, height, thickness, width, weight, distance, speed and so on. In preschool, what children need to know and compare is usually the common continuous quantities in these lives. Therefore, the "quantity comparison" involved in this paper mainly refers to the comparison of continuous quantities.