A substantial amount of research indicates that male students significantly outperform female students in terms of their ability and motivation to learn the subject of physics. In order to investigate the mechanism of external evaluation and physics learning motivation on students’ conceptual understanding of physics, this paper selected a sample of 252 high school students and analyzes the formation mechanism of gender differences using a structural equation model. The model shows that physics identity can significantly and positively predict students’ physics conceptual understanding level, while learning interest and self-efficacy have no significant effect on it. External evaluation is an important reason for the significant difference in physics identity between male and female students. Female students perceive a lower degree of recognition from others, which disrupts the formation and development of their physical identity, thereby further affecting their performance in physics learning.

With the promotion and implementation of the new college entrance examination system in our country, the elective subjects for students are becoming increasingly diverse. This paper aims to explore the motivational differences between male and female students in choosing physics under the new college entrance examination context. The research has found that although the new policy encourages students to choose subjects based on their interests and abilities, external factors such as restrictions on undergraduate major selection have a significant impact on subject selection decisions. Especially for female students, they face greater external pressure when choosing subjects, but their choices are more rational, with clearer future career planning. In contrast, male students have a more emotional motivation to choose subjects due to their love for physics. Although the number of female students choosing physics has not decreased under the new system, this trend does not continue into university, indicating that short-term external motivation is not sufficient to determine long-term career choices. This study provides strong theoretical and empirical support for the formulation and practice of education policies. It is recommended that the education department deeply understand the influencing factors to ensure that students can make the best choices.