On the Immediate and Delayed Effects of Interactionist Dynamic Assessment on Grammar Development: A Case Analysis of an Iranian EFL Learner

The purpose of this study was to investigate the effect of dynamic assessment (DA) on grammar development of a beginner foreign language learner whose L1 was Persian. For this purpose, two versions of Oxford Placement Test of Grammar were used: One as the pre and posttests and the other for teaching grammar through interactionist DA. At first, the participant was pretested to assess her knowledge of grammar before the treatment. During the study, interactionist DA was used to provide mediation to the learner depending on her needs. A posttest was conducted two days after the last session to observe the immediate effect of DA. Four weeks later the same test was also administered to observe the delayed effect of the treatment. Item-by-item analysis of the questions showed that DA was effective both in terms of its immediate and delayed effect. The microgenetic analysis revealed useful information about the potential of the learner which was not achievable in nondynamic assessment.