本研究使用準實驗設計法，探討合作學習策略對提升國小四年級不同學業成 就學生論證能力的成效。研究對象包含採合作學習策略教學之實驗組56人，以 及採一般教學之對照組56人。研究結果顯示：（1)實驗組及對照組學生之後測平 均數均高於前測平均數，並達到顯著（實驗組：—6.72,p= .000< .001 ;對照組： t=2.67,p=.010< .05)，且實驗組學生的後測平均數高於對照組學生之後測平均 數，並達到顯著(F=14.443,p=.000< .001)。（2)實驗組高、低分群學生的後測平均 數均高於前測平均數，並達到顯著（實驗組高分群：t=3.68,p= .001< .01 ;實驗 組低分群：t=6.29,p= .000< .001);對照組高分群的後測平均數高於前測平均數， 並達到顯著(t=2.73,0= .011< .05)，但對照組低分群的後測平均數與其前測平均數 則無顯著差異(t=1.20,0= .240> .05)。(3)實驗組高、低分群的後測平均數均分別高 於對照組高、低分群的後測平均數，並達到顯著（高分群：F=4.381,P= .041< .05 ; 低分群：F=9.30,P= .004< .01)。由本研究結果可知，合作學習策略在提升學生的 論證能力上較一般教學為佳，且它能有效幫助低學業成就學生改善學習成效。

The study investigated the effects of cooperative learning strategy on elementary studnets5 argumentative abilities. A quasi-experimental design was conducted to study the effects of cooperative learning strategy on the argumentative abilities of high- and low-achievement fourth graders. The participants of the study consisted of 56 students receiving cooperative learning strategy in the experimental group and 56 others receiving traditional strategy in the comparison group. The results showed that the mean of posttest was significantly greater than that of pretest for both groups (experimental group: t=6.72, p=.000<.001; comparison group: t=2.67, p=.010<.05), and the mean of posttest of the experimental group was significantly greater than that of the comparison group (F=14.443, p=.000<.001). It was also found in the experimental group that the mean of posttest was significantly greater than that of pretest for both high- and low-achievement students (high achievers: t=3.68, p=.001<.01; low achievers: t=6.29，p=.000<.001). In the comparison group, the mean of posttest was significantly greater than that of pretest for high-achievement students (t=2.73, p=.011<.05), but not low-achievement ones. Furthermore, both high- and low-achievement studnets in the experimental group significantly outperformed their counterparts in the comparison group (high achievers: F=4.381, p=.041<.05; low achievers: F=9.30, p=.004<.01). These results suggested that the cooperative learning strategy could enhance students5 argumentative abilities better than the traditional teaching strategy, especially for low-achievement students in improving their learning achievement.