Using value-added data from the Los Angeles Unified School Districts, the researchers determine individual teacher effect estimates and investigate their stability across models. This study also investigates the instructional practices of a sub-sample of 30 highly effective and 30 less effective sixth-grade mathematics teachers. Five classroom lessons are videotaped per teacher. The videotapes are coded and analyzed by researchers who are blind to the value-added effectiveness of the teachers. The reliability of measured teaching practice will be investigated by applying hierarchical linear models. Practices of highly effective and less effective teachers will be compared through analyses of variance and regression models.
