Policymakers face dilemmas when choosing a policy, program, or practice to implement. Researchers in education, public health, and other fields have proposed a sequential approach to identifying interventions worthy of broader adoption, involving pilot, efficacy, effectiveness, and scale-up studies. In this paper, we examine a scale-up of an early…

Teachers choosing between different models to facilitate students' understanding of an abstract system must decide whether to adopt a model that is simplified and striking or one that is realistic and complex. Only recently have instructional technologies enabled teachers and learners to change presentations swiftly and to provide for learning…

The concept of scaled achievement tests is discussed and a method of selecting those items of a test that form the most scalable (i.e., having the highest coefficient of reproducibility) subset is presented. Sometimes called a monotonic-deterministic model, this type of test assumes that the test items may be sequentially ordered. To determine the…