Traditional psychometric methods have primarily been developed and applied in the context of high-stakes, large-scale testing. However, these methods are increasingly being used with classroom assessments, including progress monitoring measures where numerous test forms are administered over the course of an academic year. This article provides an overview of progress monitoring and describes a new method for evaluating equating in longitudinal contexts, one that is based on a comparison of results from multilevel models of raw and equated scores. The method is demonstrated using scores from 15 reading fluency tasks administered to 231 students in a longitudinal assessment system.