本研究主要目的在探討GeoGebra 融入八年級三角形的全等單元對學生數學學習成就及學習動 機的影響。採準實驗研究法，抽樣八年級學生兩班共九十六人進行一週內八節課的教學實驗。其 中一班為實驗組，實施電腦輔助教學；另一班為對照組，實施傳統講述式教學。以三角形的全等 單元成就測驗量化資料為主，樣本個別訪談的質性資料為輔，來瞭解學生的學習成就；以數學學 習動機量表的前、後測來瞭解學生數學態度的改變情形。 分析研究資料後，發現以下的結果：一方面，GeoGebra 電腦輔助教學對學生學習三角形的全等 單元學習表現，實驗組顯著優於對照組。另一方面，GeoGebra 電腦輔助教學對實驗組學生數學 學習動機，實驗前後有顯著差異；學生更了解三角形的全等性質、能夠增加學生數學的學習動機 和興趣、對程度中下的同學成績能有所提升，學生大多喜歡此上課方式。

This research aimed to study the influence of applying GeoGebra to the instruction in congruence of triangles on the learning achievement and learning motivation of the eighth-grade students. It applied both qualitative and quantitative methods. The subjects of this research were 96 eighth-grade students from two classes at a private junior high school in Tainan City. At the end of the instruction, the grades in “the Mathematics Learning Achievement Test of Congruence of Triangles” and “Scale of Mathematics Learning Motivation” were analyzed with SPSS 21.0. Besides, semi-structured interviews were carried out and analyzed in order to provide supportive interpretation, comprehend the feedback and feelings of students and the implementation difficulties of teachers. The research results are as follows: On one hand, the experimental group made a significant difference in their learning achievement in the congruence of triangles.On the other hand, the experimental group made a significant difference in their learning motivation. Learning with GeoGebra makes students understand the congruence of triangles more easily, reinforce the motivation and interests of learning math for students, and improves the grades for the middle-level and low-level students.The majority of the experimental group enjoy using the GeoGebra-based computer-assisted instruction.