This article reports on the collaboration of six states to study how simulation-based science assessments can become transformative components of multi-level, balanced state science assessment systems. The project studied the psychometric quality, feasibility, and utility of simulation-based science assessments designed to serve formative purposes…

Federal legislation such as "No Child Left Behind" mandated that students with disabilities be included in accountability standards, creating an important responsibility to fairly assess all students, even those with disabilities. Consequently, a sense of urgency was placed on the entire educational system to ensure that these students…

In practice, vertical scales have been continually used to measure students' achievement progress across several grade levels and have been considered very challenging psychometric procedures. Recently, such practices have been drawing many criticisms. The major criticisms focus on dimensionality and construct equivalence of the latent trait or…