Across all six quarters of the study, there was a strong relationship between the Predicted Grade and actual grade for each student. These data support the claim by Freeman et al. (2007) that the Predicted Grade model is a robust index of student ability and preparedness across quarters and years. A significant heterogeneity in Predicted Grades across quarters was observed: of the 15 pairwise tests, only six were not significantly different, and these crossed levels of course structure.