The computational thinking is one of the important elements of the core accomplishment of the information technology subject. The new curriculum standard has established the "subject concept" system of information technology. In this paper, the basic model of "concept class" is put forward, and the whole subject theory system is constructed from the basic concept. We design scenarios, meaningful and valuable questions, guide students to think deeply in computational thinking mode, help them form computational thinking consciousness and improve computational thinking ability in analyzing and solving problems.