Dynamic Assessment and Its Implications for RTI Models

Dynamic assessment refers to assessment that combines elements of instruction for the purpose of learning something about an individual that cannot be learned as easily or at all from conventional assessment. The origins of dynamic assessment can be traced to Thorndike (1924), Rey (1934), and Vygotsky (1962), who shared three basic assumptions (Grigorenko, 2009). The first assumption is that conventional assessment does not work for children who have diverse educational and cultural experiences. The second assumption is that we should be interested more in where children can be tomorrow if given adequate education or intervention, rather than in where children are now given their previous educational history. The third and final assumption is that the reason for assessment lies in intervention, and consequently, that the results of assessment should have direct implications for selecting or modifying interventions. Obvious parallels exist between fundamental assumptions of dynamic assessment and those of recent response-to-intervention (RTI) models (see Grigorenko, 2009, for a comprehensive and insightful recent comparison between dynamic assessment and response to intervention). RTI models can be used as the basis of service delivery and also as a source of assessment information (Fletcher & Vaughn, 2009). Arguments in support of using RTI models as a source of assessment information mirror the three key assumptions of dynamic assessment. In the context of eligibility determination for special education services, the traditional aptitude-achievement assessment model has been criticized as a “wait to fail” model because most children with learning disabilities are not identified and provided special education services until the end of first grade or later. However, it is unlikely that adopting an RTI model for identification will speed up the process, and might even delay it. Even proponents of a prominent role of RTI models in identification of children with learning disabilities do not suggest that assessing response to intervention is sufficient for identification (Fletcher & Vaughn, 2009). Rather, consistent with the consensus of the Learning Disabilities Summit (Bradley, Danielson, & Hallahan, 2002), identification requires a comprehensive individual examination in addition to review of a child’s response to intervention (Fletcher, Lyon, Fuchs, & Barnes, 2007). If we assume that a comprehensive individual exam will not be scheduled until a child has not responded to three tiers of instruction/intervention, each each lasting 12 weeks, formal identification is unlikely to be speeded up relative to the traditional aptitude-achievement discrepancy model. This is not an argument for the traditional aptitude-achievement discrepancy model, which has been criticized justifiably on other grounds, and it should be pointed out that an advantage of an RTI model is that children receive intervention prior to formal identification. The point is merely that contact with special education personnel and services is unlikely to happen sooner under an RTI model. Might dynamic assessment be a faster way to obtain information that is provided by assessing response to intervention and is not available from conventional assessment? This question motivated the contributions to this volume of the Journal of Learning Disabilities.