There are broad and narrow meanings of curriculum. In a broad sense, curriculum refers to the sum of all disciplines (i.e. teaching subjects) stipulated to achieve the training goal of the school or refers to the sum of various activities of students under the guidance of teachers. For example, middle school curriculum, primary school curriculum. A course in a narrow sense refers to a certain subject. Like math class and biology class. In this way, the narrow curriculum has become synonymous with the teaching subject (discipline). With the development of related disciplines and the in-depth study of curriculum essence, the connotation of curriculum has undergone profound changes. Curriculum not only refers to those explicit and formal teaching and education contents, that is, explicit courses, but also refers to those implicit and informal teaching contents that have a subtle influence on students, that is, implicit courses. Courses include all the in-class teaching contents organized according to the curriculum arrangement, as well as all kinds of extracurricular teaching contents organized in cooperation with in-class teaching; Courses are not limited to the static collection of subjects, but also include the overall arrangement of teaching order, process and time limit. So far, in a nutshell, curriculum refers to the sum of educational contents and process arrangements selected by schools to achieve educational goals, including various disciplines taught by schools and purposeful and planned educational activities.