以英語為母語以及非英語為母語之教師，兩者間之協同教學國家級計劃，從1990年代開始在日本、韓國及香港各地執行。過去十年，台灣地區共有兩個相關計劃：一個位於中部某縣轄市；另一個則在北部地區，由該地方教育局與某知名學術基金會合作執行。關於這類的計畫，目前已有文獻探討執行上的困難，主要包括文化歧見、老師教學效能、與行政單位之運作問題，但其實卻並無整體評析之深入研究可供參考。 本研究遵循質化與量化的方法，針對北部之計畫為對象，深入評析中外師協同教學執行一年後之師生學習成效。研究首先以量化方式以成就測驗與態度問卷了解計畫中80名四年級與六年級小學生的英文學習成果、他們對英文的態度以及學習動機。另外又以訪談、課室觀察以及教學日記蒐集資料，分三組追蹤調查六位中外師之專業成長，藉衛考斯基的社會文化理論做分析，而文化體認方面，則以第三向度觀點，了解不同文化背景的老師之發展。 研究結果顯示此項中外師協同教學計劃對學生學習有正面作用，但程度則多有不同。學生之閱讀與聽力有成長，四年級學生受益又比六年級學生更多，但成果則因時間較短而稍顯淺薄。另一方面，中外教師在專業知識與文化體認上有顯著成長，可以說是本計畫最大受益者。 整體而言，計畫單位對中外師雙方合作關係之培養具備完善的機制，而在文化體認方面又有一群能夠以持平立場看待文化差距的諮詢專家，為中外師創造第三向度合作空間，使雙方能夠大方擁抱兩種文化且無需掩飾彼此之不同。這些設計使計劃更有效能，整體執行方式具參考價值。 / National co-teacher programs involving native English speaker teachers (NESTs) and non-native English speaker teachers (NNESTs) have been in operation since the 1990’s in Japan, Korea and Hong Kong. Two major programs have been established in Taiwan in the last ten years, one by a city government in the central part of Taiwan, the other by the education bureau of a rural county in the north, in collaboration with a well known academic exchange foundation. The cultural, pedagogical and administrative challenges such schemes face are well documented but there has been little evaluation of the benefits for stakeholders This study focused on the program in northern Taiwan and followed a mixed methods approach in order to trace learning gains from co-teaching for teachers and students over the course of one year. Students’ gains in English proficiency and changes in attitude and motivation were measured in a quantitative study involving over 80 4th and 6th grade students who were tested and surveyed. A triple case study investigated growth in professional knowledge and cultural awareness in three teaching pairs through interviews, class observation and teacher journals. Teacher learning was studied through the prism of socio-cultural theory and growth in cultural awareness from the perspective of thirdness. The program was found to have a positive effect on students, but in varying degrees. Student scores in both reading and listening proficiency improved while their attitudes and motivation were positive. Proficiency gains were greater among 4th graders than 6th graders, but the results also showed that for students, the impact of a one year program is relatively shallow. Teachers grew considerably in both professional knowledge and cultural awareness and were the greatest beneficiaries of the program. This study also found that the effectiveness of the program was facilitated by certain enabling mechanisms which nurtured the relationship between NESTs and NNESTs. Cultural awareness was facilitated by a culturally fair panel which helped create third spaces where teachers could embrace both cultures without hiding the differences between them.