探究一位效能教師教學概念生態的教學表徵與學生科學概念學習之分析研究

Abstract

摘要

本研究旨在以Chi（19921）及Chi等人（1994）的本體分類論的觀點探究一位效能教師在進行科學概念教學時會選用哪些教學表徵。此外，高、中、低成就組的學生在面對不同類型的教學表徵下，對於科學概念學習的成效為何。

根據上述觀點研究者選取一位台北市某國中效能教師和12名國中二年級學生作為研究對象，並將教學單元「化學反應」、「反應速率和化學平衡」中的科學概念依照屬性的不同分成「物質概念」和「過程概念」。然後，將教師在進行科學概念教學時所使用的教學表徵分為「靜態表徵」和「動態表徵」兩大類；在學生方面，從教學前問卷晤談和教學後的試題晤談中，比較學生概念學習的成效和概念轉變的歷程。研究結果發現可以從教師的教學表徵和學生概念學習兩個面向來看。分述如下：

（一）效能教師的教學表徵 教師在概念教學上，不論是「物質概念」或「過程概念」，他所呈現的教學表徵除了常態教學表徵-「靜態表徵A組」外，最常使用「靜態表徵B組」來輔助教學。當教師在進行過程概念教學時，還會大量地使用「動態表徵」來協助同學進行概念學習，這顯示此為效能教師會使用多樣化、多重性表徵來呈現教學概念。另外，研究者特別觀察到教師在面對「自評學生困難學習概念」教學時，不論是物質或過程概念，他都會使用五種以上不同的靜態或動態表徵來呈現單一概念的教學情境。

教師的教學表徵種類雖然是以靜態表徵中的科學邏輯陳述最多，但是教師認為使用「動態表徵」可以幫助學生克服困難學習的概念。因為，研究者發現此位教師在科學概念的教學上一定會使用「靜態表徵」，有時會依照概念的內容難易程度和屬性的不同選用「動態表徵」來搭配教學，尤其是在面對「教師自評學生困難學習概念」教學時，教師對於「動態表徵」的選用率會增加。

（二）學生的概念學習 當教師使用的教學表徵呈現多樣性、多重性時，學生概念學習表現愈好，尤其是中成就組學生，往往學習成效與高成就組差不多。此外，若使用動態表徵教學，本研究發現中、低成就組學生的學習成效會明顯提升。而高成就組學生對於「靜態表徵」的接受度遠優於中成就組、低成就組。這是由於高成就組學生本身具有比較強的學習動機，即使面對「靜態表徵」也會主動去接受、理解；而中、低成就組學生學習動機比較弱，往往較被動。因此，當教師呈現「動態表徵」時，學生會受表徵的影響產生不同的學習動力。當然，不同種類的「動態表徵」，其帶動學生學習動力的強弱也不同。此外，本研究發現了四個「強」的動態表徵分別是：角色扮演、解決問題-生活化、示範實驗和類比。

從本研究一位效能教師的教學表徵與學生學習成效的研究結果，希望成為一些從事科學教育的教師們在教學上的參考。尤其是面對不同學習成就的學生，教師呈現教學表徵的種類更顯重要。Abstract

The purpose of this study is to investigate the instructional representations during scientific concept teaching of an effective teacher based on the conceptual theory of ontological categories by Chi and Chi et al. Besides, the author would like to know the learning effectiveness on scientific concept by the students from different grades under different type of instructional representations.

Based on the perspectives mentioned above, the researcher had chosen twelve 8th grade junior high school students and one effective teacher as study subjects, conducted through two chapters from Chemistry, which were “Chemical Reaction” and “Chemical Reactivity and Equilibrium”. This study analyzed and classified the scientific concepts of these two chapters into “matter concept” and “process concept”, while the instructional representations of the teacher was also classified as “static representations” and “dynamic representations”. This study also compared these students’ conceptual learning effectiveness and inner conceptual structure by using the Pre-test and Post-test. The result of this study could therefore be viewed from the teacher and students’ perspectives mentioned above:

(A) Instructional representations of an effective teacher

Both matter or process concept used in the normal teaching of a teacher included static representations A and also static representation B, combined with much dynamic representations to help the conceptual learning of students. The phenomenon reflected the variety and multiplicity of instructional representations of the teacher. Meanwhile, the researcher observed the effective teacher would use more than five static or dynamic representations to present a single concept among those difficult concepts.

Although much of the instructional representations were based on the scientific logic narration of static representations, the teacher still felt that using dynamic representation could help students conquering difficult concepts. The researcher disclosed that the effective teacher would selectively choose dynamic representations in combination with static representations during concept teaching, especially among those rated as difficult concepts to be learnt. Dynamic representations had been shown to be chosen frequently by the teacher.

(B) Concept learning of students The efficacy of conceptual learning of the students improved in response to the variety and multiplicity of instruction representations provided by the teacher, especially in the mid grade students, whose learning result ultimately had been similar to high grade students. Meanwhile, this study also found that using dynamic representation to represent concept would improve learning effectiveness of the low grade students and those students with high grade coped well with static representation than low and mid grade students .This is due to the stronger initiative among high grade students comparing those with low and mid grade students. The latter population was tend to be more passive. Therefore, different level of learning motivation could be generated during dynamic representation given by the teacher. Four strong dynamic representations were found in this study which were role playing, problem solving, experiment demonstration and analogy.

This study provides references for teachers who involve themselves in science education based on the outcome of the research about instructional representations of an effective teacher. It emphasizes the importance of different strategy of instructional representation to cope with students of variable learning ability.