A new vision of science learning described in the "Next Generation Science Standards"--particularly the science and engineering practices and their integration with content--pose significant challenges for large-scale assessment. This article explores what might be learned from advances in large-scale science assessment and…

This study investigated the application of multidimensional item response theory (IRT) models to validate test structure and dimensionality. Multiple content areas or domains within a single subject often exist in large-scale achievement tests. Such areas or domains may cause multidimensionality or local item dependence, which both violate the…