Individual liberty combines two essential connotations, freedom from other's arbitrary will and possibility to act according to one's own will. The preface of the dissertation argues that social development lies on and contributes to individual liberty. Four social factors, knowledge and modernity, national welfare, traditional civilization and market economy, shape the direction of the elementary school, in which children are endowed with more liberty. Children's liberty is affected by both social development and the development of children. Children's liberty and development are ends and means each other. At one hand, children's liberty are essential condition of development, the other hand the ends of the children's development is liberty.Social development interact with transformation of elementary schools, and children's liberty related to children's development, which forms the background knowledge to comprehend the children's liberty in elementary schools. Due to this viewpoint, this dissertation mainly inquires three questions as following:Firstly, what is children' s liberty? The first part of this dissertation probes into this problem and concludes that children's liberty holds same connotations of individual liberty. The implication of children's liberty is composed of three related inscapes, which are dignity, rights and choice. Children's dignity has two aspects, the negative one and active one. Ihe former is that children should not be treated as means and instruments, the latter is that children should acquire rationality and morality through involved in certain civilization. Children's rights refer to the citizen's rights endowed by laws. Children's choice is the possibility to choose the value of their lives for their own sake and more responsibility for their lives. The liberty of children is not absolute but relative, and lies upon children's sense, obedience to rules and ability to responsible for their action.Secondly, what is the status quo of children's liberty in elementary schools? Schools can contribute to children' s liberty without doubt. However, many factors ignore and trespass on the liberty of children nowadays. The second part of the dissertation indicates that factors from three aspects, obstacles to children's dignity, rights and choice.Thirdly, how can the elementary schools ensure and facilitate the liberty of children? The third part of the dissertation focus on the feasible strategies within the schools, that is to ensure the liberty of children by balancing and sharing the power in schools and checking the educational methods, and facilitate the liberty of children by reforming the methods of intellectual education and moral education.In short, the dissertation can be mainly concluded as following: Children's liberty and development are reciprocal. The liberty of children composed of three factors, dignity, rights and choice. Nowadays, children's liberty is restricted and impeded by many factors in the elementary schools, therefore we should reform the education to ensure and facilitate the liberty of children.