The phenomenon that engineering students have little interest in theoretical knowledge learning is more and more apparent. Therefore, most students fail to understand and apply theories to solve practical problems. To solve this problem, the importance of improving students' interest in the learning theoretical course is discussed firstly in this paper. The definitions and essence of interest are also studied and discussed. Secondly, the challenges that most teachers have to face when they carry out teaching activities are analyzed. Then, the theorem of Kolb educator role are discussed and applied to solve the challenges. Finally, the corresponding role that teachers should play when they face the different challenge is presented and some effective approaches on improving students' interest are provided