In the teaching design of deep learning in primary school mathematics, the determination of unit learning theme focuses on the core content of mathematics, and fully reflects the subject attributes and learners' characteristics. The design of deep learning in primary school mathematics is based on the learning theme of understanding the essence of the core content, which does not completely break the logical framework of the original subject curriculum content and teaching materials, nor can it go beyond the cognitive order of mathematics knowledge, but is based on the overall analysis of the core content of mathematics, but the unit learning theme is to expand and supplement learning resources by adjusting the presentation order of the content.

Based on the characteristics of primary school mathematics, the themes of unit learning in deep learning can be divided into two categories. The first category is the unit learning theme based on the core content determined by curriculum standards and textbooks, such as the understanding of integer addition and subtraction within 20, the understanding of area and area calculation of length and square, and the second category is the unit theme generated by the integration of interdisciplinary fields with real problems as the background, such as urban traffic problems, money and us.