Policy Brief

On Growth Models, Time for California to Show Some Improvement

Growth Models
Morgan Polikoff
University of Southern California
California is one of just two states (with Kansas) that does not use a student-level growth model to measure school performance. This brief lays out a number of common beliefs about growth models and provides evidence that these beliefs are inaccurate or unsupported. In so doing, the brief makes a positive case that the state should adopt such a model and replace the current "change" metric in the California School Dashboard. Two specific models—student-growth percentiles and residual-gain growth models—would be a dramatic improvement over what the state currently uses and would much more validly identify schools succeeding and in need of support.