The purpose of this study is to explore the curriculum development process of the instruction of career development in a junior high school. Three important points are mentioned in this paper: 1) The development of curriculum should be based on teacher's understanding on students base-line knowledge and curriculum contents, 2) Teachers can monitor the process of curriculum development by enhancing their professional knowledge and abilities, 3) Teachers can accrue new understanding of their curriculum through their re-conceptualization of the curriculum contents as well as students feedback, and further improve their instruction effectiveness.