This study focuses on the factors which explain Abu Dhabi Education Council’s (Adec) English curriculum choice in grade ten and eleven public high schools in the United Arab Emirates (UAE). It investigates the challenges its implementation poses for teachers personally and professionally. The study is exploratory and interpretive and is based on the perceptions of 12 male teachers; 6 Arab teachers of English and 6 “native” English speaking teachers at 3 boys’ public high schools in the Abu Dhabi emirate. Data were gathered through lengthy semi-structured interviews with teachers, analysis of Adec curriculum and assessment documentation as well as open, non-participant classroom observations. The findings show the current curriculum, modelled on that used in NSW mainstream schools in Australia up until the end of 2014 is an inappropriate choice for students learning English as a foreign/second language in a school environment where all other subjects are taught in Arabic. This in turn provides a range of challenges for teachers who are unable to implement the course content as it was intended or the learner / learning-centred pedagogical approaches promoted by the curriculum and assessment documentation. The study recommends a realistic assessment of students’ language needs be undertaken as a top priority and, based on these findings, English classes streamed according to students’ language proficiency; with curriculum and assessment designed to reflect the various stages of learning. Ability grouping would enable specialist teachers to target areas of strength and weakness, thus countering the boredom and frustration currently experienced by many students. The study also recommends future stakeholder consultation, an in-depth orientation for newly hired teachers and professional development for incumbent teachers in scaffolded language instruction.