中學自然科教師的氣體擴散概念及其預測學生氣體擴散測驗表現之研究

Abstract

本研究主要是藉由二階層氣體擴散診斷試題，探討58位不同背景的中學自然科教師及414位國中及高中學生在氣體擴散的概念、中學自然科教師對其學生在氣體擴散概念上的了解情形以及教師對學生的了解和學生實際表現的之間的差異。 研究結果顯示，高中自然科教師在氣體擴散診斷試題中的表現較國中自然科教師表現佳，且師範院校、教育大學或研究所畢業的教師在本研究中的表現也優於一般大學或研究所畢業的教師，主修理化科的自然科教師在本研究中的表現也優於非理化科的教師，不同年資的自然科教師在本研究中的表現則沒有顯著的差異；教師在氣體擴散試題的四個次概念中，以「氣體擴散速率與分子量的關係」表現最好；在答題信心部分，高中教師的答題信心高於國中教師，全體教師在氣體擴散概念中的得分與答題信心程度呈現顯著正相關。 在學生表現的部分：高中學生在氣體擴散診斷試題中的表現顯著優於國中學生的表現；在氣體擴散試題的四個次概念中，以「密閉容器兩種氣體擴散的運動情形」表現最好，且高中學生的表現顯著優於國中學生；在答題信心部分，高中學生的答題信心高於國中學生，全體學生在氣體擴散概念中的得分與答題信心程度呈現顯著正相關。 在教師預測學生表現的部分：經分析發現，教師在氣體擴散概念中預測學生的表現與學生實際作答情形有差異，教師在「密閉容器兩種氣體擴散的運動情形」以及「氣體擴散速率與分子量的關係」對學生表現的預測雖有差異但較接近學生實際回答情形。 在本研究中也發現，當同樣的氣體擴散概念以不同試題類型出現時，不論是國中生、高中生或是在教育現場服務的自然科教師都可能改變自己原本的想法而改用其他的方式解釋題目，教師預測學生回答時，亦會因為試題類型的不同而選擇不同的回答。

The purpose of this study was to use two-tier diagnostic instrument of gas diffusion to examine high school science teachers and students’ responses on the gas diffusion and how teachers predicted their students’ test performance. The participants in this study were eighth graders (n=223) and eleventh graders (n=191) students and science teachers (n=58) in junior and senior high school. The results revealed that high school science teachers’ performance was better than junior high school teachers. Also, teachers graduated from Teachers College performed better than teachers graduated from general university. In addition, we found that teachers majored in physics and chemistry performed better than other majors. Teachers’ best performance at four sub-concept of gas diffusion was "relations between the molecular weight and diffusion rate". Senior high school teachers’ answering confidence was higher than junior high school teachers. We also found that there was a significantly positive relation between all teachers’ performance in the gas diffusion test and answering confidence. As for students’ performance, we found that high school students’ performance was better than junior high school students. Students’ best performance at four sub-concept of gas diffusion was "closed container movement of the two gas diffusion ". Also, senior high school students’ answering confidence was higher than junior high school students. In addition, there was significantly positive relation between students’ performance on the gas diffusion test and answering confidence. As for teachers’ prediction on students’ performance, the results revealed that II science teachers predicted students’ performance differently depending upon the concepts relating to gas diffusion. In this study, we found that regardless of teachers or students, they tended to change their responses to the questions when the contexts of the questions were changed even though they were assessed the similar concepts about diffusion of gases. Educational implications are discussed.