為瞭解兒童在認知發展行為的表現，本研究招募國小一年級學童56名，五年級學童32名參與實驗進行。應用囚犯困境賽局與最後通牒賽局之架構設計兩個遊戲，來檢測兒童在合作與分享行為之表現。分析受試者之背叛比率、提供數量、拒絕比率等實驗資料，來檢測年齡、性別以及長幼關係是否會造成顯著影響。 實驗結果發現： （1）年齡較大兒童較傾向較合作且拒絕比率較低，這個結果和認知發展理論的結論一致。 （2）受試者資料在性別效果的假設檢定結果都不顯著。 （3）年齡較小兒童的平均提供數量都大於一半，這個結果和最後通牒賽局的理論預測相反。（4）對手為不同年齡時的背叛比率和拒絕比率都比對手為同年齡時低，這個結果支持國小開設混齡教育課程。 / This paper studies children’s behavior in an ultimatum game and a prisoner’s dilemma game with 56 children of age 7 and 32 children of age 11. With the experimental data of defect ratio, offer quantity and rejection ratio, we tested the age, sex and seniority effects under these two games. The experimental findings are as follows. （1）The older children are more cooperative and have lower rejection ratio than younger ones. These results are consistent with the developmental psychology theories. （2） We observe no significant sex effect in the three tests. （3） For younger children, the average offer quantity is higher than fifty percent, this is different from theoretical prediction and literature results.（4）We found that for pairs consisting of subjects of different ages, The defect ratio and rejection ratio are lower than pairs of the same age subjects. This evidence may provide support for mixed-age education program for some courses in elementary school.