This chapter considers how Dynamic Assessment (DA), especially in a computerized form, may be applied to understand the abilities and needs of school-aged learners of English as an additional language. As DA is relatively new in the field of language assessment, and computer-based applications of DA have only just begun to be explored, we are unaware of any empirical studies applying this framework to contexts involving young English language learners. The chapter considers an especially important avenue for future assessment practice with L2 learners, including young learners of English: computerized DA. Initial exploration of delivering mediation in DA through a computerized system focused on listening and reading abilities among university learners of L2 Chinese, French, and Russian. To understand the scoring procedures, recall that mediation in our computerized DA (C-DA) tests, as in DA research more generally, conceives of learner responsiveness as an indication of their development.