zahra Rezaei Fard - Department of English, Shahreza Branch, Islamic Azad University, Shahreza, Iran
Mohsen Shahrokhi - Department of English, Shahreza Branch, Islamic Azad University, Shahreza, Iran
Mohammad Reza Talebinejad - Department of English, Shahreza Branch, Islamic Azad University, Shahreza, Iran

This study embarked on investigating the effectiveness of teaching ESP vocabulary via flipped classroom on improving Iranian students’ vocabulary learning. In addition, the attitudes of ESP learners towards the use of flipped classroom were investigated. In this study, a quantitative procedure was followed to collect and analyze data . In so doing, ۶۰ ESP participants studying English in Payame Noor University were selected non-randomly based on their performance on Oxford quick placement test. All the participants were divided into two equal groups consisting of ۳۰ participants and a pretest was administered. The participants of the experimental group received instruction through flipped classroom. The control group received vocabulary instruction through the conventional method that was popular in the university. A posttest was given to the participants of both groups in order to check the students’ vocabulary learning. To investigate the students’ attitudes towards using flipped classroom, a ۱۰-item questionnaire was distributed among the participants after the treatment phase of the study. The results of one-way MANOVA showed that implementing flipped classrooms has significant effects on Iranian students' vocabulary learning in ESP courses. Furthermore, the participants of the experimental group acknowledged that implementing flipped classrooms has positive effect on their attitude in ESP courses. The findings regarding the effectiveness of flipped classroom and its prospected implications in developing vocabulary learning can pave the way for better communication in an ESP context and community.

flipped classroom, vocabulary learning, learners’ attitudes, ESP learner