Abstract: The phenomenon of credit hour compression in undergraduate mechanics courses is common, which brings challenges to both learning and teaching. This study analyzed the causes and effects of credit hour compression on the quality of classroom teaching. Combined with the effects of artificial intelligence and the characteristics of post-2005 college students under the medium of “digital +”, which discussed and put forward some teaching reflections on how to ensure the quality of classroom teaching by considering the teaching content, teaching progress and design, teaching methods and skills.