"Primary School" is written by Lu Kun, a famous educator and thinker in the Ming Dynasty, and is an important educational enlightenment book in ancient China. The book takes Confucian ethics as the basic content, and aims to educate children to cultivate good moral character and behavioral Xi from an early age, and learn the basic principles of being a person, doing things, and getting along. 
Through concise and concise texts, the book expounds the traditional virtues such as morality, benevolence, loyalty, and filial piety in simple terms, and is an enlightenment textbook suitable for children to read. The Elementary School is divided into two volumes, with a total of thirty short essays. The first volume focuses on the cultivation of moral character, while the second volume focuses on the teaching of common sense and behavioral norms. Each essay vividly describes various virtues and behavioral norms in concise and clear language, making it easy for children to understand and accept. In "Primary School", Lu Kun emphasized the importance of moral education, believing that morality is the foundation of human nature and the foundation of being a human being. 
He advocated "ruling the world with filial piety", emphasizing the virtues of filial piety to parents and respect for elders. At the same time, he also taught children to be honest and trustworthy, to be benevolent, and to cultivate good moral character. In addition to moral education, Lu Kun also pays attention to children's common sense of life and behavioral norms. In "Primary School", he teaches children to develop good life Xi, such as diligence, neatness, and frugality. He also reminded children to stay away from bad Xi, such as laziness, playfulness, selfishness, etc., so as not to affect their physical and mental health. It is worth mentioning that "Elementary School" is also quite distinctive in terms of educational methods. Lu Kun advocates leading by example, requiring teachers and parents to influence children with their words and deeds, so that their words and deeds are consistent. He also advocated inductive education, through inspiration and guidance, so that children spontaneously develop good moral character and behavioral Xi. 
In short, "Primary School" is an enlightenment textbook with profound traditional cultural heritage, which takes moral education as the core, covers many aspects such as common sense of life and behavioral norms, and aims to cultivate children's good moral character and behavioral Xi. The book not only provided a valuable educational resource for children in ancient times, but also has important reference value even today.