摘要:AbstractIntegrating content and language is not a new idea but one that is becoming increasingly more practiced in language classrooms around the world and one that is continuously evolving. According to the Eurydice European Unit (2006), one of the goals for using this approach besides the obvious objective of mastering a language as well as learning subject matter, is to prepare for life in a more internationalized society. The purpose of the present research is to identify the relationship between learning and developing vocabulary and learning English in CLIL classes among Iranian EFL learners of SAMA schools. In SAMA schools all subjects are taught in Persian except mathematics and science, which are taught in English. The research method was quantitative, and the research sample was all the students of SAMA school in Tabriz city (40 students) and students of an ordinary school (40 students). Data were gathered through a researcher-made tool which consisted of 50 items. Results showed that the students of SAMA school have the ability to develop and retain vocabulary better than ordinary school students because of the Content and Language Integrated Learning (CLIL) method and textbooks which they are taught for science and mathematics subjects.