Mahdieh Noori - PhD candidate of TEFL, Department of English language and literature, Alzahra University, Tehran, Iran
Ali Mohammad Fazilatfar - Associate professor of TEFL, Department of English language and literature, Yazd University, Iran
Golnar Mazdayasna - Associate professor of TEFL, Department of English language and literature, Yazd University, Iran

Blended learning as a supplementary to traditional face-to-faceteacher-centered classes, has achieved the attention of English asforeign language (EFL) leaning scholars and practitionersworldwide (Tosun, 2015). To test the effectiveness of blendedEFL instruction in General English for Academic Purpose(GEAP) courses, the current study investigated the results of aone-semester-long blended EFL learning course by comparingthe general English achievement of a randomly-selectedexperimental general EFL learning group (with online messenger app-based instruction) with a peer control group (without suchinstruction) in a state university in Iran. The results ofIndependent-samples t-test estimates of the current study with apost-test only control group design revealed that the students whobenefited from blended instruction significantly outperformedthose in the control group in terms of their general Englishknowledge. Moreover, the results of some follow-up semistructuredinterviews with 15 participants of the experimentalgroup corroborated the effectiveness of blended GEAP classes ingiving learners an opportunity to customize their learningpractices. The results further implicated some positive andnegative aspects of blended EFL practices in GEAP courses.

Blended learning, EFL achievement, EFL learners General English for Academic Purpose