A central objective of science education is to foster a profound comprehension of fundamental scientific principles among students. Research has shown that a highly integrated knowledge structure is a key factor in achieving a deep understanding. This research has developed a friction force conceptual framework to model students' different understandings of friction force from a knowledge integration perspective. Utilizing the established conceptual framework, this study devised and implemented an evaluation of friction force among a cohort of 598 grade-10 students in China. The assessment outcomes were then analyzed quantitatively and qualitatively. The results show that the conceptual framework model effectively represents the knowledge structures of students at different levels of knowledge integration, and the students' understanding of friction force can be divided into three levels: novice, intermediate, and expert. Furthermore, emphasizing the passivity of friction force can help students gain a deeper understanding of the concept of friction force, thereby forming a more comprehensive knowledge structure. This study provides an effective strategy for students to progress from novices to experts.