Abstract: The reform of the teaching mode of general education is an important way for many colleges and universities to train undergraduates with all-round development. At present, many colleges and universities regard the reform of the teaching mode of general courses as an important way to train high-quality undergraduates in an all-round way. Based on the constructivism learning theory, PBL teaching model takes problems as the starting point, guides students to gradually improve their ability to analyze and solve problems step by step through autonomous learning and group cooperation, and provides a reform paradigm for improving student's learning motivation. In this study, 192 students from a double first-class university were selected to conduct a 16-week PBL teaching experiment in a general education class. The results show that, compared with the control class, the learning motivation of the experimental class is significantly improved under the PBL teaching model, in which the internal motivation is the main driving force, the strengthening effect of external motivation is enhanced, and the difference between internal and external learning motivation is reduced. The research results provide further reference and reference for the localized application of PBL teaching model in general courses and the promotion of student's learning motivation.

Key words: General course, PBL teaching model, Intrinsic motivation, Extrinsic motivation, Experimental design, Undergraduates