Zahra arabsarhangi - Ministry of Education, Tehran

The present study was conducted to demonstrate the effect of one of the popular social media tools, Instagram, on the improvement of Iranian EFL learners' vocabulary knowledge. Instagram launched in October 2010 and quickly gained popularity around the world. It allows its users to share photos and 15-second videos with their followers. Nowadays, the availability of this social media channel for practicing a language and delivering the materials in different formats of photos and videos with a variety of filters and added captions has turned it into a useful tool for enhancing vocabulary. In addition, the time demanding nature of vocabulary learning and classroom time limitations have led some teachers to use this ideal platform to boost their students' motivation to increase their vocabulary knowledge. The participants of this study consisted of 60 students who were studying in grade one in two different high schools in Tehran. They were divided into one control and one experimental groups. While the activities of the experimental group were done in the instagram environment, those in the control group were performed in the class following the norms of any English class without technology. The students in the experimental group wrote different sentences on the comment part of the classroom's Instagram page based on the newly learned vocabularies and were corrected by the teacher. On the other hand, the students in the control group do the same activities without the Instagram. The same vocabularies were taught by the same teacher in both classes. After the 2- month treatment period, the participants sat for the posttest. The results of an analysis of variance revealed that learning vocabulary in Instagram environment led to better vocabulary enhancement

Social media tools, Instagram, Vocabulary enhancement, EFL learners