Dear Commons Community,

Nicholas Kristof has a column today in the NY Times today on the value of a good teacher.   Kristof  cites  a research paper by economists Raj Chetty, Harvard University,  John N. Friedman, Harvard University, and Jonah E. Rockoff, Columbia University, that underscores  that the  difference between a strong teacher and a weak teacher lasts a lifetime.

“Having a good fourth-grade teacher makes a student 1.25 percent more likely to go to college, the research suggests, and 1.25 percent less likely to get pregnant as a teenager. Each of the students will go on as an adult to earn, on average, $25,000 more over a lifetime — or about $700,000 in gains for an average size class — all attributable to that ace teacher back in the fourth grade. That’s right: A great teacher is worth hundreds of thousands of dollars to each year’s students, just in the extra income they will earn…Conversely, a very poor teacher has the same effect as a pupil missing 40 percent of the school year.”

The Executive Summary of the paper addresses specifically the issue of “value added” in teacher evaluations.

“Overall, our study shows that great teachers create great value and that test score impacts are helpful in identifying such teachers. However, more work is needed to determine the best way to use [value added] VA for policy. For example, using VA in teacher evaluations could induce counterproductive responses that make VA a poorer measure of teacher quality, such as teaching to the test or cheating. There will be much to learn about these issues from school districts that start using VA to evaluate teachers. Nevertheless, it is clear that improving the quality of teaching – whether using value-added or other tools – is likely to have large economic and social returns. “

Tony