本研究旨在探查兩位理化教師酸鹼中和主題教學的學科教學知識（Pedagogical Content Knowledge, PCK）面向內涵和關係。蒐集資料主要有：晤談與教學討論的錄音、教學設計稿、教學錄影。依紮根理論分6 個步驟分析，包括：形成概念、精緻概念、編碼資料和概念、分類概念、統整展現各面向的教學要素、確認PCK 各面向關係。研究發現如下：（1）教師展現PCK 的主要面向和文獻相符，包括：教學取向、關於學生理解科學的知識、科學課程知識、教學表徵和策略知識與評量知識。所展現PCK 的教學要素呈現相似與相異內涵，相異內涵是基於「教師如何教」、「學生學什麼和如何學」觀點。（2）教師展現PCK 面向的關聯呈現階層性單向影響，教學取向為上階層，關於學生理解科學的知識和課程知識居中，教學策略和表徵知識與評量知識為下階層且相互影響。（3）教師展現PCK 面向的關聯係透過相關教學要素連結，其中「科學教學本質」、「教師角色」、「學習策略」和「學習疑難」是關鍵。（4）教師展現PCK 品質倚賴於各個面向的統整程度。

This study aimed to explore the contents of two teachers’ Pedagogical Content Knowledge (PCK) as it unfolded in teaching practice and to build up portrayals of their PCK on the teaching of a unit on acid-base neutralization. Interrelationships among contents in theses dimensions were also investigated. Using qualitative methodology for data collection, a range of data were collected from transcripts of stimulated interviews and audio recordings of meetings, drafts of teaching plans, and transcripts of classroom videos. Analysis of data went through a series of steps, starting from analysis of collected data, to formation of concepts, categories, instructional elements, and finally to the formulation of research claims. The findings of this study are summarized as follows: (1) The main dimensions of the teachers’ enacted PCK are consistent with literature including teaching orientations, students’ understanding of scientific knowledge, curriculum, instructional representations and strategies, and assessment. There are similar and different characteristics between the instructional elements of case teachers’ PCK along different dimensions. The different characteristics are based on teacher’s knowledge about ＂how should teachers teach,＂ ＂how should students learn＂ and ＂what should students learn＂. (2) There is a hierarchical and causal relationship between the various dimensions of PCK. Instructional orientation is located in the upper level. Knowledge of students’ understanding of scientific and knowledge of curriculum are located in the intermediate level. The instructional representations and strategies and assessment are located in the low level, bearing mutual influence with each other. (3) The pattern of a case teachers’ enacted PCK is an integrated result of the interrelationships among the instructional elements belonging to the various knowledge dimensions. Within the case teachers’ PCK, there were four instructional elements including ＂nature of science teaching,＂ ＂role of teacher,＂ ＂ learning strategies ＂and＂ students’ learning predicaments＂ which were found to have strong impacts on teachers’ PCK. Therefore the above four instructional elements are the keys to teachers’ instructional decisions. (4) The quality of PCK depends on the degree of integration of the interrelationships among the various dimensions of PCK.