1. Introduction

This timeline is concerned with Dynamic Assessment (henceforth, DA) as it has been taken up and elaborated in contexts involving the teaching, learning, and assessment of learners of second languages (L2s). DA is distinguished by its insistence that an individual's independent performance of assessment tasks reveals only part of his/her abilities, namely those that have completed their development at the time of the assessment; insights into abilities that have begun to emerge but have not yet fully developed can be determined according to an individual's responsiveness to particular kinds of support, referred to as mediation (e.g., reminders, leading questions, hints, provision of a model, feedback), offered during the assessment as difficulties arise (Haywood & Lidz, Reference Haywood and Lidz2006). In this respect, DA differs from more conventional distinctions in assessment, such as that between assessments concerned with the results of previous learning (‘summative assessment’) and those intended to provide information relevant to subsequent instruction (‘formative assessment’). Instead, the embedding of an interactive, instructional element within the assessment procedure allows for the possibility of expanding the evidential basis upon which summative interpretations of learner abilities are made; that is, the results encompass previous learning that has resulted in both complete and partial understanding of relevant concepts. At the same time, DA serves a formative function in so far as interaction allows insights into the underlying sources of learner difficulties and the kind of support to which they are most responsive (Sternberg & Grigorenko, Reference Sternberg and Grigorenko2002).

DA enjoys a dual heritage in both Sociocultural Theory (SCT), as formulated by Russian psychologist L. S. Vygotsky (Reference Vygotsky, Rieber and Carton1987), and in the writings of Israeli educator Reuven Feuerstein and his Mediated Learning Experience (MLE) framework (Feuerstein, Rand, & Hoffman, Reference Feuerstein, Rand and Hoffman1979). SCT understands psychological development as occurring through processes whereby individuals internalize forms of mediation including forms of reasoning, conceptual knowledge, counting systems, and most notably, language. Such mediation regulates psychological activity, enabling us to understand, think, and act in new ways. In other words, the genesis of our psychology is in the social world, in our engagement with others who mediate the world to us and us to the world, allowing us to contribute in ways that go beyond our current abilities. Of course, as Vygotsky (Reference Vygotsky1978) explained, because individuals have a history of prior experiences, their psychological activity is mediated even when they are functioning alone. Under such circumstances, the activity reflects abilities that have fully formed at the present time. In contrast, functioning cooperatively with others reveals the range of abilities that are still emerging, the Zone of Proximal Development (ZPD).

As the reader may appreciate, the scope of SCT is not limited to language learning but rather it provides an account of human consciousness and its development. That said, much of Vygotsky's (Reference Vygotsky, Rieber and Carton1987) own empirical work that was central to elaborating his theory was conducted with children to understand the processes through which internalization occurs and individuals develop the capacity to regulate their psychological activity. It was through this work that Vygotsky (Reference Vygotsky and Rieber1998) noted specifically the relevance of the ZPD to education: (a) recognizing when and why an individual's independent functioning is inadequate to meet present demands (i.e., diagnosing development) and (b) functioning alongside learners to promote their development (that is, providing support or teaching attuned to learners’ present abilities and aimed at moving them forward). One may choose at particular times or under certain circumstances to focus on mediating to probe responsiveness and understanding as an assessment or mediating to guide learners toward new ways of thinking and acting. In both cases, it is mediation that is central to development-oriented assessment and teaching.

For his part, Feuerstein was focused not on devising a theory of psychological development but with determining appropriate interventions to help young children with special needs (Feuerstein et al., Reference Feuerstein, Rand and Hoffman1979). While Feuerstein formulated his ideas independent of Vygotsky's theory, they bear striking similarities, and the procedures elaborated by the former are fully commensurate with the latter's view of abilities and their development (Miller, Reference Miller2011). Both emphasized the centrality of others in mediating learner engagement in activities and with specially designed materials for the purpose of developing their abilities. While Vygotsky (Reference Vygotsky, Rieber and Carton1987) considered development across the lifespan, including during early childhood, schooling, and adulthood, Feuerstein's MLE has focused predominantly on promoting general forms of perception, remembering, and reasoning held to be precursors to school learning (Kozulin, Reference Kozulin1998). Nonetheless, both thinkers maintained that observation of a person's independent performance of tasks can at best reveal their development up to the present and that identification of abilities that are partly formed as well as underlying difficulties requires joint functioning or cooperation.

In the general and special education research literatures, this orientation to assessment came to characterize several procedures that invoked the ideas of Vygotsky or Feuerstein or both and that are collectively referred to as DA (see Lidz & Elliott, Reference Lidz and Elliott2000). It is difficult to pinpoint the earliest use of DA in an L2 educational context. Since the 1980s, L2 scholars had drawn upon SCT to better understand learner development of language abilities in instructional settings (e.g., Frawley & Lantolf, Reference Frawley and Lantolf1985). While not overtly framed as DA, Aljaafreh and Lantolf's (1994Footnote *) study of an English language tutor's interactions with learners as they reviewed learner writing is widely referenced in the L2 DA literature. Aljaafreh and Lantolf grounded their research in the ZPD, analyzing the tutor's efforts to remain sensitive to learner difficulties and responsiveness as they jointly reviewed written work. The authors identified a range of mediating behaviors, which they noted could be organized along a continuum from most implicit to most explicit. They argued that rather than providing mediation in a haphazard manner or simply providing only a single form of mediation to all individuals, it is more effective to negotiate with learners according to their responsiveness. For Aljaafreh and Lantolf, mediation should be contingent upon learner need for it and should be removed as learners develop greater capacity to regulate their own functioning. These recommendations underscore the instructional function of the ZPD. From the perspective of DA, determining the extent of mediation learners require forms an essential part of the diagnosis, indicating how near they are to independent functioning.

Another early article in the L2 field that began to draw attention to DA was a conceptual study by McNamara (Reference McNamara1997). The author challenged assessors to consider the possibility that L2 oral abilities targeted by their procedures might be reconceived as an emergent feature of interaction, as occurs in communicative contexts outside of assessment situations, rather than as strictly the knowledge or characteristics (i.e., traits) of individuals. In developing his position, he discussed the tenet in MLE that full diagnosis requires engagement with the learner and shared responsibility for performance.

In the early 2000s, studies began to appear that overtly referenced DA in L2 contexts. For instance, Schneider and Ganschow (2000*) built upon DA research with learners with special needs and extended this work to examining difficulties experienced by learners with dyslexia as they studied L2 English and German. Kozulin and Garb (2002*) explicitly referenced both Vygotsky's conceptualization of the ZPD and Feuerstein's MLE framework in their implementation of DA with secondary school English as a foreign language (EFL) learners in Israel. Kozulin and Garb's research also made an influential contribution by proposing a formula for capturing differences between learner independent performance on tests and their performance when mediation is available, a contrast they discuss as learning potential. Finally, in a paper delivered at a meeting of the American Association for Applied Linguistics, Antón (Reference Antón2003, later published as Antón, 2009*) reported initial results from a study employing DA to place learners at an appropriate level of study in a university L2 Spanish program.

It was also around this time that Lantolf and colleagues (e.g., Lantolf & Thorne, Reference Lantolf and Thorne2006) increasingly began to consider the potential of SCT as a basis for organizing language curricula and educational activities. This view, subsequently referred to as praxis, regards theory as the appropriate orienting basis for practice, while practice is the essential testing ground to confirm, develop, and revise theory (see Lantolf & Poehner, 2014*). DA is one of the major lines of work associated with this shift toward SCT praxis. The other, which has come to be known under the heading concept-based language instruction, reorganizes L2 curricula and teaching practices according to Vygotsky's (Reference Vygotsky, Rieber and Carton1987) analysis of the potential for instruction to promote learner psychological development through the introduction of abstract conceptual understandings in all areas of study. Concept-based language instruction is not discussed here, and interested readers are referred to a timeline in Language Teaching devoted to that topic (Lantolf, Xi, & Minakova, Reference Lantolf, Xi and Minakovaforthcoming).

The first in-depth study of L2 DA that embraces a praxis orientation is Poehner's (2005*) doctoral thesis. That project employed DA principles in a one-to-one procedure assessing oral proficiency among advanced undergraduate university learners of L2 French. The framework for Poehner's study was also elaborated through two articles (Lantolf & Poehner, 2004*; Poehner & Lantolf, 2005*) that identified major trends, models, and approaches in the general DA literature and discussed them in relation to Vygotsky's formulation of the ZPD. All of this work was further developed in Poehner's (2008*) subsequent monograph on L2 DA.

In the time since these initial publications, research into L2 DA has been pursued by scholars with expertise in SCT, language testing and assessment, classroom interaction, and teacher education. Studies have been conducted with learners of English and common European languages as well as less commonly taught languages. Populations of learners have ranged from primary school children to adults and from learners at the earliest stages of language study to those with advanced proficiency. In some cases, DA procedures have focused upon particular L2 abilities, such as reading or listening comprehension, while others have been linked to curricular goals, emphasizing mastery of content taught in a course. The following recurring themes or issues have emerged in L2 DA research, and the papers included in this timeline fall into one or more of these categories:

• A. Overviews of theoretical foundations of Dynamic Assessment and major approaches. Unsurprisingly, as a new innovation in L2 assessment, DA has been included in various overviews of approaches in the field. This work has been kept up to date through such papers appearing every couple of years. These papers have also allowed for consideration of new theoretical connections as well as identification of conceptual and practical challenges as well as important directions for future work.

• B. Dynamic Assessment in L2 instructional contexts. Given the relation between assessing and teaching that is integral to DA, many L2 DA studies have been carried out in instructional settings (i.e., tutoring environments and classrooms) and they have often been undertaken in cooperation with teachers. In some instances, teachers serve as the assessors as well and they are involved in determining assessment targets and formats. Moreover, following the distinction introduced by Lantolf and Poehner (2004*) Regarding approaches to mediation, teachers may choose either an interventionist or interactionist form of DA.

  • B1. Interventionist Dynamic Assessment. In this approach mediation is planned beforehand, and in fact every mediating move made by a teacher is usually scripted and these moves are arranged hierarchically from most implicit to most explicit. In this way, teachers provide mediation in a lock-step fashion, progressing from one mediating move to the next. This approach has the advantage of allowing teachers to carefully and precisely determine the amount of mediation particular learners needed on a given occasion.

  • B2. Interactionist Dynamic Assessment. Mediation in this approach is not scripted although careful planning is usually still required. Mediation emerges dialogically from the exchanges between the teacher and learner as they jointly engage in instructional activities. Although mediation is not fully standardized, it does typically proceed along a continuum of implicit to explicit depending upon learner needs and responsiveness as these become apparent during the interaction.

  • B3. Teacher perceptions of and practice with Dynamic Assessment. Reflecting the trend toward collaborations with teachers in L2 DA research, some studies have sought to understand teachers’ experiences employing DA and how these relate to their thinking about teaching, assessing, learning, and language.

• C. Conceptual advances in Dynamic Assessment. By extending DA into the L2 field and engaging with a range of populations and language abilities, this has necessarily required consideration of the ways in which important concepts in assessment (e.g., generalizability, validity, reliability) must be accounted for in DA and perhaps reconceptualized. Other conceptual advances include studies with implications for understanding of SCT principles.

• D. Computerized Dynamic Assessment and Dynamic Assessment in computer enhanced language learning contexts. As computer-based language tests have become more widespread, research into the integration of mediation in a computerized DA procedure allows the assessment to be administered simultaneously to large numbers of learners. Researchers have also investigated the applicability of DA in contexts characterized by instructional technologies, including most recently mobile learning.

In this timeline, there are more entries in certain categories than others, although this should not be taken to imply that categories with relatively few entries are less important. DA is still relatively new to the L2 field, and a small number of authors are responsible for many of the studies conducted to date. As the number of L2 researchers engaged in DA continues to grow, we might expect that certain categories will witness a rise in the number of studies. We might also anticipate that the coming years will give rise to potential new themes and issues in L2 DA research.

Related to this latter point, we wish to acknowledge that the focus of this timeline is specifically DA research concerned with contexts of L2 learning. As the preceding discussion makes clear, there is a much broader DA literature that encompasses many areas of education and cognitive psychology. Advances may well occur as L2 scholars engage with that work, and vice-versa. One area that would seem especially fruitful in this regard is the body of work devoted to DA with bilingual learners. Due to space constraints and to our interest in L2 rather than bilingual education contexts, that work is not included in this timeline. We also wish to alert readers to the considerable interest in DA in recent years among L2 researchers in both Iran and China. Unfortunately, relatively few papers from those research communities have appeared in English language journals and could be included here. It is hoped that this situation will change in the years ahead. Indeed, the extension of DA to these new linguistic and cultural contexts may well lead to exciting theoretical insights and methodological advances.