Everyone knows that a good teacher makes a difference, but establishing who the good teachers are, and what difference they make, has long been a problem. A new study by economists at Harvard University attempts to answer these questions. They analysed the school records and earnings information for 2.5 million children, and found that, when a high “value added” teacher joins a new school, results for their class improve.
Having a high value-added teacher (in the top 5%) for one year raises a child’s cumulative lifetime income by $50,000. How this information is used is clearly a matter of policy, but any system that aims to reward good performance while supporting or punishing poor performance would need to be carefully designed and tested. An interesting article about the study can be found here.
Source: The long-term impacts of teachers: teacher value-added and student outcomes in adulthood (2011), American Economic Review