How Much Do Early Teachers Matter?

We present new estimates of the contributions of early grade teachers on later grade test outcomes. We obtain estimates of 8th-grade math achievement from models that include teacher indicators in grades 4-8. Consistent with prior literature, these “stacked” value-added models show there is fade-out of teacher effects as students advance from grade to grade. But our estimates show far less fade-out than prior estimates; in fact, we find a substantial portion of the impact of having a good early-grade teacher continues all the way though 8th grade. We estimate the difference in contributions to 8th grade tests between an effective and ineffective 4th-grade teachers is about one-third the difference between an effective and ineffective 8th-grade teachers.