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Hot for the Wrong TeachersWhy are public schools so bad at hiring good instructors?

By Ray Fisman
Posted Friday, July 11, 2008, at 7:50 AM ET
Is it possible to predict who will teach well?

PS 49 in Queens used to be an average school in New York City's decidedly below-average school system. That was before Anthony Lombardi moved into the principal's office. When Lombardi took charge in 1997, 37 percent of fourth graders read at grade level, compared with nearly 90 percent today; there have also been double-digit improvements in math scores. By 2002, PS 49 made the state's list of most improved schools. If you ask Lombardi how it happened, he'll launch into a well-practiced monologue on the many changes that he brought to PS 49 (an arts program, a new curriculum from Columbia's Teachers College). But he keeps coming back to one highly controversial element of the school's turnaround: getting rid of incompetent teachers.

Firing bad teachers may seem like a rather obvious solution, but it requires some gumption to take on a teachers union. And cleaning house isn't necessarily the only answer. There are three basic ways to improve a school's faculty: take greater care in selecting good teachers upfront, throw out the bad ones who are already teaching, and provide training to make current teachers better. In theory, the first two should have more or less the same effect, and it might seem preferable to focus on never hiring unpromising instructors—once entrenched, it's nearly impossible in most places to remove teachers from their union-protected jobs. But that's assuming we're good at predicting who will teach well in the first place.

It turns out we aren't. For instance, in 1997, Los Angeles tripled its hiring of elementary-school teachers following a state-mandated reduction in class size. If L.A. schools had been doing a good job of picking the best teachers among their applicants, then the average quality of new recruits should have gone down when they expanded their ranks—they were hiring from the same pool of applicants, but accepting candidates who would have been rejected in prior years. But as researchers Thomas Kane and Douglas Staiger found, the crop of new teachers didn't perform any worse than the teachers the school had hired in more selective years.

This unexpected result is consistent with the findings from dozens of studies analyzing the predictors of teacher quality. Researchers have looked at just about every possible determinant of teaching success, and it seems there's nothing on a prospective teacher's résumé that indicates how he or she will do in the classroom. While some qualifications boost performance a little bit—National Board certification seems to help, though a master's degree in education does not—they just don't improve it very much.

It's worth keeping in mind that economists study changes in test scores, not love of learning or comprehension of course material—it's possible that some of the teachers who look good to researchers are just good at teaching to the test. Needing some measure of success in the classroom, economists mostly rely on "value added" in test scores—that is, how much students' scores improve as a result of a year in a teacher's classroom. Since researchers study entire school systems over many years, they're able to separate out how much of an individual student's improvement is due to personal circumstance and how much is the result of inspirational teachers. If a student's test scores increase year after year, then no teacher gets any credit for it; similarly, no one's on the hook for a bad student's repeated failure to progress.

What economists have found is that only one thing tells us how much a teacher will boost his students' test scores next year: the amount he raised test scores in previous years. A good teacher this year will very likely be a good teacher next year. Unfortunately, when making hiring decisions, principals rarely have that information at their fingertips. Most hiring decisions are made before applicants have a teaching record. And an individual school has neither the necessary data nor the ability to run the complicated regression analyses needed to discern whether an experienced teacher has had a positive effect on his students in the past.

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Ray Fisman is the author of Economic Gangsters: Corruption, Violence, and the Poverty of Nations (with Edward Miguel). He is the Lambert Family professor of social enterprise and research director of the Social Enterprise Program at the Columbia Business School.
Photograph of blackboard by Digital Vision.
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Notes from the Fray Editor

This was an excellent, full Fray with many many great posts and arguments. Although people disagreed with one another and with the article, often very strongly, the threads mostly stayed calm and polite: an object lesson in online posting. Almost everyone wanted to contribute to the discussion, to make useful points, to make suggestions or to relate personal experiences – to the benefit of anyone reading. Posts below are just to whet the appetite: read the full Fray to get the full experience.

Comments from the Fray

I have been a public school educator for 13 years. Firing bad teachers would improve my morale immensely. It's very frustrating to know that the lazy/racist/apathetic/clueless idiot down the hall is getting paid to be a marginal-at-best babysitter. Bad teachers do inordinate damage to our profession as well as students and make everyone's job even more difficult. To paraphrase something I read in Harper's many years ago, no one works harder than a good, conscientious, caring teacher, but there's no one lazier than a bad one. (This is probably true in many other fields as well.)

I would love it if good principals with common sense (another kettle of fish) spent more time in all of our classrooms. Many do not out of a fear of being accused of micro-managing, time constraints, and/or an "ignorance is bliss" mentality. Conscientious teachers welcome observation, professional guidance, and constructive criticism if they know they are truly valued for their hard work, being treated fairly, and given real power to do what is best for their students and their school. Under these more ideal conditions, average teachers also become better, and ambivalent or stumbling teachers emerge from the gray areas with the skill and motivation they need to continually improve their classrooms.

--herdbird

(To reply, click here)

The obvious, sensible, tried-and-true method of educating pupils and students well is to provide a wide variety of subjects, from rigorously academic to useful trade to the esoteric and artistic, taught in a variety of styles and methods, in small classes, in secure schools without distractions and have the students live in stable, economically secure households. Doing that would require considerably more money than we want to spend and demand a restructuring of our economy to provide the stable and economically secure homes. I don't see us willing to do that for our children…

The canard about the difficulty of firing a tenured teacher was once again repeated. Any principal who can't successfully go through the steps to fire a truly bad teacher should themselves be fired. It is neither that onerous, nor particularly lengthy. It happens every year in most school districts in the land. I've seen several fired over the years, more often for teaching in a way that annoyed the principal than actual bad teaching, but fired nonetheless. Firing does involve more than at private industry, but that protection is well-founded and ever more necessary. Often, the teachers principals want to fire the most are the ones the school and the students need most for those teachers are the one asking questions instead merely following orders, the ones trying new ways and ideas, instead of trodden the well-travelled path.

We can fiddle with details, but until the military is holding bake sales to buy needed battle ships and schools are funded enough that underpaid teachers aren't buying pencils and paper, we aren't really committed.

--MacAdviser

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(7/11)

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