學科教學知識的研究多集中在科學及數學，少數以第二語言或外語學習；至於國語文領域，特別是要為讀寫能力奠基的國小低年級研究則佔極少數。本研究以一位資深國小低年級教師為例，探究其在教學前、教學中、教學後的教學推理歷程，分析其轉化成功與否之原因。本研究參與者為盈芬老師（化名），在同一所學校的低年級任教15年。研究進行近一年時間。教師於教學前分析教材並撰寫教案，與研究者討論後再調整；教學進行中由研究者觀察並錄影記錄，教學後再進行一次訪談，瞭解教師對教學的反思，並寫成研究札記。本研究是以其中文體相近的三個單元做為主要分析對象。分析時反覆比較資料，標示教學轉化，並對比其教學行動及反思，理解其教學推理及決定。研究發現教師在轉化原型教材為教學教材的歷程中，形式表徵的轉化較主題內容順利。低年級學生不易理解抽象概念及感受，教師使用問答進行教學時屢屢受挫，最後以演戲及體驗進行轉化才順利達成教學目標。而在寫作方面，教師均以課文延伸的清楚結構引導，逐步加入學生熟悉的生活題材，鼓勵學生以圖畫、注音和國字表達思考，值得低年級教師參考。

Related research on pedagogical content knowledge (PCK) is mostly in the field of science and mathematics, with few investigations into ESL/EFL or foreign language learning, and even fewer on language arts in Chinese language in lower elementary grades. This study explored the pedagogical transformation and reasoning of an experienced first-grade teacher before, during, and after her teaching of reading and writing and analyzed why the transformation succeeded or failed. The research participant is Ms. Yin-Fen (pseudonym), a veteran of fifteen years at the same school teaching the lower grades. The study lasted for almost one year. The teacher first transformed the content of the textbook into lesson plans and then was interviewed about her plans. During the teaching, the class was videotaped and audiotaped, as well as observed. After each lesson, the researcher interviewed the teacher again about her evaluation and reflection. This study picked three units in the same genre to analyze. All data were transcribed and analyzed using the constant comparison method between the plan and action to better understand the teacher’s pedagogical reasoning and decision, and why the transformation was successful or not. The results show that the transformation on the genre schema was more successful than the content/theme. The lower graders had difficulties in understanding abstract concepts when the teacher used questioning techniques. It was not until drama and experiential activities were applied that the students came to understand the content better. In terms of writing, the teacher gradually added themes related to students’ experiences after they had managed the genre schema. The teacher also encouraged students to express themselves in writing through drawing, Mandarin Chinese phonetic symbols, and characters, which are worth noting for other lower grade teachers.