How much is a good teacher worth?
As we've previously reported, Stanford University economist Eric Hanushek has gotten a lot of mileage out of his argument that America could vault into the league of high-performing nations like Finland and Singapore if it did just one thing: get rid of the least-effective 5 to 10 percent of teachers, as measured on standardized tests, and replace them with average performers.
In a new article in the journal EducationNext, Hanushek spells out the economic and political implications of such a move. (The journal calls itself non-ideological, but it's supported by the right-leaning Thomas B. Fordham Institute and Stanford's Hoover Institution, where Hanushek works as a senior fellow.)
There are lots of numbers here, which he says are based upon credible studies. One shows the difference in lifetime earnings for individual students who score one standard deviation above average on high school tests ($110,000 to $230,000,) and another reveals the difference in economic impact of a single teacher in the 84th percentile of effectiveness, compared to one in the 50th percentile ($400,000.)
Do the math, he says, and you get some truly hair-raising numbers.
"Closing the achievement gap with Finland would, according to historical experience, have astounding benefits, increasing the annual
growth rate of the United States by 1 percent of GDP. Accumulated over the lifetime of somebody born today, this improvement in achievement would amount to nothing less than an increase in total U.S. economic output of $112 trillion in present value. (That was not a typo—$112 trillion, not billion.)"
How could America pull off this feat? Hanushek holds out little hope that better teacher training or recruitment could do the trick, based on past experience. Nor does he seem encouraged by the "dominant strategy" of helping current teachers improve through professional development and mentoring.
"While such efforts undoubtedly help some teachers, there is no substantial evidence that certification, in-service training, master’s degrees, or mentoring programs systematically make a difference in whether teachers are in fact effective at driving student achievement," he writes.
What's left? Hanushek said districts could overhaul their teacher evaluation systems to discern between high- and low-performing teachers, and "deselect" those on the bottom.
"They would need recruitment, pay, and retention policies that allow for the identification and compensation of teachers on the basis of their effectiveness with students," he writes. "The teachers who are excellent would have to be paid much more, both to compensate for the new riskiness of the profession and to increase the chances of retaining these individuals in teaching. Those who are ineffective would have to be identified and replaced."
Does this sound familiar? Hanushek's name pops up in some of the research behind Hillsborough's efforts to reform teacher evaluation with the Bill & Melinda Gates Foundation. But superintendent MaryEllen Elia and other district officials hope to prove him wrong on the question of recruiting and mentoring, saying it's not possible to "fire your way to excellence."