This study is an attempt to examine if dynamic assessment of speaking with focusing on form comparing to static one, has any statistically significant effect on more rule internalization of male and female Iranian EFL intermediate learners. Unlike other skills, however, speaking has not received much focus as long as the application of DA is concerned. More specifically, the focus on spoken grammar seems to have attracted minimal attention from the scholars in the field. Also in recent years, traditional standardized objective achievement tests have been criticized to be inappropriate and invalid way of measuring the students' academic competencies (O'Malley and Valdez Pierce, 1996).Therefore, given these problems with which we are faced in the traditional ways of testing, DA as a performance based test along with the teacher’s mediation during the testing, can reduce the learners’ anxiety, create a positive attitude toward assessment and learning and provide an authentic context to testing as far as ‘communicative era’ is considered. Being used as the formative assessment, DA hinders the materials to be accumulated for final exam as well.