本研究旨在探討「注意力經濟」脈絡下，線上音樂實踐社群（Online Music Communities of Practice, OMCoP）之運作機制及其對教師專業發展的影響。研究採個案研究法，以Facebook公開社團「大方分享—音樂教學共備社群」為研究對象，分析2021至2025年間971則貼文互動資料，並訪談七位核心成員與第一線音樂教師，希望可以針對日益稀缺的「注意力資源」，找到教師專業學習的新藍海。本研究主要發現有三：一、該社群已由疫情期間的應急支援平台，逐步轉型為具備共同領域、社群互動與共享實踐之成熟實踐社群。二、在演算法與資訊過載環境下，教師專業學習已由「知識獲取」轉向「注意力配置」，依據「注意力方程式」中的注意力商數，媒體使用者的高專注度和意圖驅動及有價值的時間投入較能有效吸引教師注意力並促成知識轉化。三、社群互動呈現「高點閱、低參與」特徵，但透過情感支持與弱連結互動，仍能形成教師專業認同與非正式學習支持系統。本研究建議未來教師專業社群應強化主題式深度對話、虛實整合互動與注意力導向之知識設計，以提升線上專業學習品質。

This study aims to examine the mechanisms through which Online Music Communities of Practice (OMCoPs) operate within the context of the attention economy and influence teachers’ professional development. A case study approach was adopted, using the public Facebook group “Dafang Sharing: Music Teaching Co-preparation Community” as the research site. Interaction data from 971 posts published between 2021 and 2025 were analyzed, and interviews were conducted with seven core community members and frontline music teachers. In response to the growing scarcity of attention as a learning resource, the study seeks to identify new pathways for teachers’ professional learning. The findings reveal that, first, the community gradually evolved from an emergency support platform during the COVID-19 pandemic into a mature community of practice characterized embodying the three core dimensions of domains, community, and practices. Second, under the influence of algorithms and information overload, teachers’ professional learning has shifted from knowledge acquisition to attention allocation. According to the Attention Equation (A = CQ + AQ), content that elicits a high level of user focus, intention-driven engagement, and meaningful time investment is more likely to attract teachers’ attention and facilitate knowledge transformation and professional learning. Third, although community interaction exhibited a pattern of high viewing but low participation, emotional support and weak-tie interactions continued to foster teachers’ professional identity and informal learning support systems. Based on these findings, future online teacher professional communities should encourage in-depth thematic discussions, strengthen integrated online-offline interactions, and adopt attention-oriented knowledge design to improve the quality of online professional learning.