類比對應對學生建構“原子結構”心智表徵之影響

The Effectiveness of Analogies in Learning of Concepts of Structure of atoms by Eighth Graders

雖然人們在日常生活中常使用類比，但卻很少察覺到它是如何產生對應關係的，而類比在科學概念學習的使用上亦是如此。因此本研究將探討類比對科學概念的學習是否有所助益？若有，類比對應又是如何影響學習？本研究以舊教材（85年度）國中二年級理化「原子結構」單元為題材，設計「含類比」及「不含類比」兩份教材，以探討類比是否有助於此單元的初次學習。研究對象為國中二年級學生20名，分為類比組和實驗組兩組，每組各10人。研究過程包括前測紙筆測驗、閱讀學習及後測晤談。本研究之結果主要有下列四點：一、類比教材有助於學生「原子結構」概念之學習，並有助於學生根據教材中科學史的發展，接受電子雲式的原子模型。二、高低成就主要的差異在於高成就組能產生較多的關係對應，特別是高階關係的對應，因而能與既有概念產生連結或進一步應用於欲學的概念上；低成就組則產生較多屬性對應，並缺乏高階關係的對應，有時因過於注重屬性對應或未能掌握關係對應的意義而產生另有概念。三、受試者對類比物的背景知識會影響類比對應的結果，而並未朝向教材預期的方向思考。四、類比圖能提供更多元領域的知識及具體的心像因而促進類比學習，但需注意圖形之選擇、避免產生誤解。綜合上述，在實際應用上，教師或教材編寫者可善用類比以促進科學概念之學習；但應詳細說明科學概念與類比物之間的對應關係，以協助學生能產生適當的類比對應及詮釋。

Although we usually use analogies in our daily life, neither do we know "how it comes" and "how it produces mapping" nor the application of an analogy to the learning of scientific concept. Therefore, this study aimed at investigating whether the analogies were helpful to the learning of scientific concepts. And if it was, how did analogical mapping influence the learning achievement? A teaching materials for learning structure of atom -one include analogies, the other did not include analogies-was designed to investigate whether the analogies was helpful to the learning. Twenty subjects of averaged ability at the eighth graders were divided into two groups-analogy and control groups. Each group was composed often subjects. The experimental procedures included a paper-and-pencil test, reading activities and post-test interviews. The results of study were: 1. This study found that the analogies were helpful to the learning of 'structure of atoms'. Also, they were able to understand the electronic cloud models of atoms via reading materials with history of atoms. 2. As to analogical mapping, there was not absolute difference between the two groups but in degree. However, the group of high achievement could generate more relational mapping, especially that of higher-order mapping. In contrast, the group of low achievement tended to generate attributive mapping and thus lack high-order mapping. 3. Students held produced alternative conceptions while using analogies and their analogical mapping and interpretations did not always correspond to teaching materials because of the influence of prior knowledge and the fact that students did not understand analogies at all. 4. Learning structure of atoms with pictorial analogies helped students construct mental images that supported their learning of abstract concepts. To sum up, teachers and editors of teaching materials can use analogies to promote the learning of science. However, the mapping of teaching materials should be explained in details to ensure that students' and teachers' mappings and interpretations of analogy are parallel. Furthermore, the design of mapping materials should base on subjects' life experiences to ensure the effectiveness of analogy.