随着《义务教育课程标准（2022年版）》的颁布，所有中小学教师都面临着开展跨学科教学活动的任务，并亟需应对来自跨学科教学的挑战。北京部分学校的教师在新课标颁布之前已经拥有开展跨学科教学的丰富经验，对于跨学科教学经验不足的教师而言具有重要参考价值。教学专长是理解教师教育教学能力的有效视角，对教师跨学科教学能力的探索研究具有启发性。以往针对教学专长的研究多在概念、结构和影响因素层面，尽管也有深入探讨教师教学专长特征与发展机制的经验性研究，但关注教师跨学科教学专长的研究还难以支撑大规模教学实践。

基于以上背景，本研究以北京市XXX区6位教师作为研究对象，以多个案研究作为研究方法，以教学专长的过程-整合观和社会建构观为主要理论视角，结合三轮次半结构化访谈，建立了教师跨学科教学专长的专长结构和社会建构分析框架。本研究根据访谈内容确定个案教师的教学专长发展阶段，从专长结构和社会建构两个角度对个案教师进行分析，探究个案教师跨学科教学专长的特征和发展机制。

本研究的主要结论（或成果）：①以过程-整合观和社会建构观的专长研究取向，结合个案教师数据所设计的专长结构和社会建构框架，能够用于分析教师的跨学科教学专长特征和发展机制；②有关专长结构特征，不同专长阶段的教师的专长结构在知识结构、教学能力层面呈阶段性质变，但处于中间阶段（合格实践者、熟练实践者）的教师反而更加容易在发展能动性和情感态度上产生起伏和改变；③有关社会建构的专长发展机制，高效浓厚教师文化氛围利于创建良好的知识共享环境，从而促进教师跨学科教学专长发展；师生共同体的结构性和学生通过作品、对话等反馈会对不同专长阶段的教师产生程度不一的影响，对于熟练实践者教师影响最大；非正式交往对跨学科教学专长的发展有重要作用，该帮助可能来自于教师的其他社会关系，也可能来自于教师与同事之间因非教学因素产生的联系，如物理距离最近，在同一办公室的教师们。

本研究佐证了专长发展非线性、高效的社会交互促进专长发展、非专家成为专家需要经历“质疑没有问题的问题”阶段和“理论知识实践化-实践知识理论化”过程等观点。本研究的新发现主要为：跨学科教学专家的生成与其一般文化知识和其他社会关系关联紧密，师生共同体的质量对跨学科教学专长发展有直接影响，非正式场合的教师对话能促进知识转移，从而促进非专家教师的跨学科教学专长发展。

最后，本研究基于研究结论，对学校与教师提出建议，并建议未来研究尝试探索教师非正式交往的知识转移机制和师生共同体中社会情感过程对教师教学专长的发展作用。

With the release of the Compulsory Education Curriculum Standard (2022 Edition), all primary and secondary school teachers are faced with the task of carrying out interdisciplinary teaching activities and coping with the challenges from it. Teachers in schools in Beijing have already had experience in interdisciplinary teaching before the new Curriculum Standard was promulgated, which is of great reference value for teachers who have not yet had experience. Instructional expertise is an effective perspective to understand teachers' teaching ability, and it is instructive to explore and study teachers' interdisciplinary teaching ability. Previous studies focused on the concept, structure and influencing factors of instructional expertise. There were few cases that deeply discussed the characteristics and development mechanism of teachers' instructional expertise, and even fewer studies focused on teachers' interdisciplinary instructional expertise.

The study took 6 teachers from XXX District of Beijing as participants, used multi-case study as the research method, made the process -integration view and social construction view of instructional expertise as main theoretical perspectives, and combined three rounds of semi-structured interviews to establish the expertise structure and social construction analysis framework of teachers' interdisciplinary instructional expertise. The study determined the development stage of the instructional expertise of the case teachers according to the interview content, analyzed the case teachers from the perspectives of expertise structure and social construction, and explored case teachers’ characteristics and development mechanism of the interdisciplinary instructional expertise.

The main conclusions (or results) of this study are as follows: (1) The specialty structure and social construction framework designed by combining the data of case teachers with the specialty research orientation of process-integration view and social construction view can be used to analyze the characteristics and development mechanism of teachers' interdisciplinary instructional expertise; (2) As for the characteristics of expertise structure, the expertise structure of case teachers in different stages of expertise presents qualitative changes in the knowledge structure and instructional ability, but the teachers in the middle stage (qualified practitioners, skilled practitioners) are more likely to fluctuate and change in the development of initiative and emotional attitude; (3) As for the expertise development mechanism of social construction, the efficient and strong teacher cultural atmosphere is conducive to creating a good knowledge sharing environment, so as to promote the development of teachers' interdisciplinary instructional expertise; The structure of teacher-student community and students' feedback through works and dialogues will have different degrees of influence on teachers at different stages of expertise, and the influence on skilled practitioners is the biggest. Informal interaction plays a significant role in the development of interdisciplinary instructional expertise. This assistance may come from other social relationships of teachers or from connections between teachers and colleagues arising from non-pedagogical factors, such as teachers who are physically closest to each other in the same office.

This study proves that expertise development is non-linear, efficient social interaction promotes expertise development, non-experts need to go through the stage of "questioning questions without problems" and the process of "practicalization of theoretical knowledge-theorization of practical knowledge" to become experts. The new findings of this study are as follows: the generation of interdisciplinary instructional experts is closely related to their general cultural knowledge and other social relations, the quality of the teacher-student community has a direct impact on the development of interdisciplinary instructional expertise, and informal teacher dialogue can promote knowledge transfer, thus promoting the development of non-expert teachers' interdisciplinary instructional expertise.

Finally, based on the research conclusions, this study puts forward suggestions for schools and teachers, and suggests that future studies try to explore the knowledge transfer mechanism of teachers' informal communication and the role of social emotional processes in the teacher-student community in the development of teachers' instructional expertise.