Teacher quality: Vital, hard to measure

“Teacher quality is the most important factor in determining how well a school will do,” says Eric Hanushek in an interview with John Merrow on Learning Matters.

. . . despite its good intentions, I think that the highly qualified teacher part of NCLB is actually its worst part. The reason is simple. We have huge measurement problems that make prior interpretations of this requirement hollow at best and harmful at worst. Teacher quality is not captured by typically discussed characteristics of teachers such as master’s degrees, teaching experience, or even certification – things that states typically monitor. Requiring such things unrelated to student performance dilutes accountability and detracts from things that would make them more effective. Fortunately, however, test-based accountability produces the student achievement data needed to assess the value-added of teachers, a more appropriate focus of policy concerns.

Reducing class size — pupil-teacher ratios are now less than 16 to 1 — is a mistake, Hanushek says.  It takes money that could be spent to pay “highly effective teachers substantially more.”

Pay effective teachers what they are worth (think six-figure salaries) but also have them teach somewhat more kids. That model is easily supported. What is not supported is paying large salaries to both effective and ineffective teachers and also reducing class sizes.

The Gates Foundation is spending its money — a lot of money — looking for ways to evaluate teacher effectiveness.

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  1. Ponderosa says:

    Today I taught my seventh graders about socialism and capitalism and the regimes of various modern countries as a prelude to teaching about the Inca and their welfare state. Only the latter would show up on the state history tests, yet I believe the former topics enriched their minds. On what test would this show up?

    A few days ago I taught about enzymes, starches, yeast, alcohol, plant breeding, the various uses of guano and other matters related, but slightly tangential to, Inca agriculture. None of this stuff will be sought on the state history exam, and yet, I’m convinced that the vocab and concepts I gave them will make them stronger readers and thinkers. How would I get credit for this?

    I am very skeptical that tests can pinpoint which teacher did what.

    Rather than browbeating us with threats of firing, how about giving us more prep time? Top performing nations give teacher 20 hours a week. We get 4. I am looking forward to a weekend filled with grading and lesson planning I was not able to do during the week. This is why most Teach for America shining stars say hasta la vista to teaching.

  2. And, why don’t we ask about evaluating the effectiveness of CPAs, electrical engineers, novelists, and street performers (all of whom had teachers by the way)?

    We are soon going to ask about improving the effectiveness of doctors.

    Lawyers, as we say, not so much.

  3. Homeschooling Granny says:

    Is teacher quality is the most important factor in determining how well a school will do? How about parents? Parents who see their kids struggling with something and step in with an explanation; who see what kids are working on and bring in their own relevant experiences, or provide book on the topic, or take the family on a field trip. One of the difference between high and low performing schools is parents?

  4. We can measure the distance to galaxies at the edge of the universe, the relationship of individual molecules in a strand of DNA, the characteristics of subatomic particles that have a lifetime measured in trillionths of a second but measuring teacher effectiveness? Now *that’s* tough.

    Come on, it’s not that measuring teacher effectiveness is such a big deal but that for a very long time teacher effectiveness simply wasn’t important and there are still plenty of people in the education sector for whom teacher effectiveness still isn’t important.

    For instance, does the average school board member get elected or not based on the quality of the teaching professionals they’re ultimately responsible for hiring? No.

    How about superintendents? Do the average superintendent, as a matter of course, get raked over the coals about the quality of the teaching staff they hired by school boards looking to hire them? No.

    Does that average principal see it as a crucial job function to make life miserable enough for the lousy teacher so they move along even if said principal doesn’t have the power to simply fire them? No.

    Maybe measuring the effectiveness of teachers really is tougher then measuring the distance to the furthest galaxy but we won’t know that until the people in a position to measure teaching effectiveness have a reason to do so.

  5. It seems to me that the single most important factor affecting teacher quality is the ISD / management structure they work under. Bad schools doesn’t mean bad teachers, it means bad management.

  6. “Today I taught my seventh graders about socialism and capitalism and the regimes of various modern countries as a prelude to teaching about the Inca and their welfare state. Only the latter would show up on the state history tests, yet I believe the former topics enriched their minds. On what test would this show up?”

    If you have managed to make the Incas interesting and relevant by placing them in context with the modern world, your kids will remember them and beat the pants off of kids that merely attempted to memorize enough to pass the test.

  7. >>And, why don’t we ask about evaluating the effectiveness of CPAs, electrical engineers, novelists, and street performers (all of whom had teachers by the way)?<<

    The effectiveness of all of these professions is measured, repeatedly. Why would you think it wasn't. And it's easy to measure; we simply look at their results.

  8. Peter is absolutely correct. We measure the effectiveness of virtually all careers by how much business they bring in. A salesperson makes a lot of sales? Boom- they are worthwhile and will get a raise. A salesperson makes very few sales? boom- get a new job. Same with practically everybody but teachers. We all get paid the same (more or less) in public schools, and there are no financial incentives to work extra hard or be especially good at your job. I call that socialism, and, like socialism, it results in reduced efficacy levels of teachers. My solution- vouchers for all students. A yearly check from the government that can only be spent on tuition. Same amount of cost but with the options we don’t have today. Then educators will be evaluated by the free market system the same as everybody else.

  9. Ponderosa says:


    a. School districts can already fire teachers at will before they get tenure. If they gave them tenure, they must have SOME ability.

    b. As an insider, I doubt that bad teachers are among the top five causes of educational underperformance. Bad TEACHING on the other hand, is a big factor, and this is committed by conscientious educators who follow the wrong-headed progressive ed prescriptions of ed school, including the half-baked ideas of reading gurus Kate Kinsella and Cris Tovani. Give our bright and hard-working teaching corps better ideas about teaching and achievement will soar.

    c. There are downsides to tenure, for sure, but there are upsides as well. For example, I am able to speak truth-to-power in my district without great fear of reprisal –and I think what I’m saying is really salutary for the superintendent to hear. In your beloved Social Darwinist scenario, I would never dare contradict the Man. I know you libertarians conceive of liberty differently, but to me this is liberty, sweet liberty. Tangible liberty.

    d. Japan has done pretty well with life-time guaranteed employment at the big companies (though this is changing). Why not reform, rather than fire, underperforming teachers? Knowing that the employer gives a sh*t about your welfare pays dividends to the employer.

    5. I urge you to question the stereotype of the lazy, dim-witted union teacher. I had a few of these when I was in school, but they have been scarce in the three schools I’ve worked in. The norm is rather a workaholic, corporate wannabe who is ashamed to be part of the union and will do almost anything the administration asks of them without question. Questioning souls like myself are rare.

    6. Checks and balances are good for the American government, preventing abuse of power. Teacher unions provide a check and some balance to the power of the superintendent, who is far from infallible.

    Things are complicated.

  10. Sweet! A debate! I’m in, Ponderosa.

    You are correct. I am a libertarian. I am also in my 13th year of teaching in a public school and, like you, very dedicated and will work hard and tirelessly. Sounds like you and I agree on the importance of education.
    However, your claim that most teachers are hard working is belied by what I have seen at my school over the last 12 years. I have observed and spoken to so many teachers that are simply bad teachers, as well as observed and interacted with teachers who are superb. The question was, “How do we measure teacher quality?” You diverged from a critique of my proposal of opening up the education business to the free market and started discussing the power relationship between individual teachers and management (principals and superintendents). Hey, there will always be bad bosses, and the way to negotiate with them is to join a union (I am a union member- have been for almost all my career) which is what people in all the other industries do as well. My question, and I did not see you address this at all, is my should education be so different and special? If the free market works to filter out bad employees and businesses all over the U.S., why would it not work for education?
    Finally, a quibble. Japan’s economy has been stagnant and even shrinking over the last ten years and shows no sign of getting better, so I am not sure where your idea of life time employment helping Japan came from. Plus, the culture os Japan is one of duty and work and respect to authority, which is why Japan has thrived in the past. A better example of how life time employment guarantees has worked is France with its mandated 35 hour long work weeks and frequent strikes and an economy that is crumbling.

  11. a) Har! Yeah, that’s got to be it. Uh, if determining teacher effectiveness is so tough how do they manage to do it when it comes to determining who gets tenure?

    b) Oh, we’re ranking ’em now? How about lousy teachers who set the stage for making a good teacher’s job more difficult by making it clear how unimportant education is? But leave us not forget the rest of the public education establishment for whom education may or may not be important depending on their personal dedication.

    c) Speak truth to power? Oh, get over yourself. The only reason for tenure in this particular situation is because skill isn’t considered valuable. If a particular teacher were responsible for sending a school to the World Series of Education you think that teacher’d need tenure?

    d) I’ve got a better idea. Let’s just assume that it’s an *education* system not a teacher-employment system and get rid of people who get in the way of the organization’s goals.

    V) Whoops! Strawman alert! Duck and cover! Worse! Strawman alert coupled with self-aggrandizing breast-beating! Duck and cover your ears to prevent unseemly laughter.

    VI) Yeah, I’m sure the union’s terribly worried about the quality of the education the kids are getting. Oddly enough, the superintendent’s about as worried about the education the kids are getting. Question is, who is worrying about the education the kids are getting and is in a position to do anything about it?

    Complicated? What’s so complicated about understanding that when no one’s on the hook for good results bad results result?

  12. Allen: it many places, tenure is based only on time, not performance. If an ineffective teacher can fly under the radar for long enough to make tenure, they’re set.

    I think that it is important to realize that student test scores alone are not enough (or even useful) in assessing teacher effectiveness. How, without standardized test scores in Spanish or Ceramic or Computer Technology would those teachers also be subject to the same assessment of teachers of English, math, and science.

    If teachers are going to be assessed for effectiveness (which I agree with), that assessment should be connected to their pay…which would mean that it must be open to all teachers, even those not assessed by high stakes tests. I believe that our Voc-Ed teachers, our elective teachers, etc., are as valuable if not more valuable than “core” teachers and deserve the opportunity to be rewarded (with better pay) by somehow demonstrating their effectiveness.

  13. Good parents and good students are just as important as good teachers. All are crucial, but only one is under the teacher’s control.

    If you are going to use test scores to evaluate teachers, then you need to evaluate all students’ IQ, executive function, and family support structure. If your students’ average IQ is 90, with poor frontal lobe function and zero family support, good luck improving those test scores.

    As for the education unions, their main function is to lobby their well-groomed pet legislators to help limit competition. No to charters, no to vouchers, no to school choice, no No NOOO!!!

    Robber barons of education in union uniforms. Charming, but just the way backs get scratched, the Chicago way don’t you know.

  14. Read up the thread Mark G, I was responding to Ponderosa who was trying imply that the conferring of tenure implied professional competence. I was calling Ponderosa on the con.

    You are right about the lack of standardized tests but their absence is due to the fact that the public education system works quite nicely, thank you very much, without standardized tests so, what needs is there of them?

    That’s the problem, that the public education system has gotten along quite well without any overt and officially-sanctioned measures of accountability for so long that the concept is foreign and frightening. In fact, as I’ve been maintaining for a while, education, as a measured, and thus crucial outcome, doesn’t figure very importantly in the professional life of anyone employed in the public education system.

    The teachers that are good are good not because being lousy gets you fired but because their pride won’t allow them to act any other way. But the system in which they work takes no notice of their skills. I’d suggest that the result is a work environment not particularly conducive to the pursuit of excellence by the professionals employed in that environment.

    The underlying problem is that the current structure of public education is hostile to the introduction of standardized testing. Standardized testing’s actually been around for a couple of decades at the state level but has, in the bulk of cases, had its fangs pulled; no one takes the tests too seriously.

    NCLB was an attempt to change that but it was building a structure of accountability on a foundation of sand. The solution is that the structure of public education has to change one in which testing is inherently a proper function of the system and confers worthwhile results.

  15. Ponderosa says:


    Thanks for your thoughtful response.

    A quick reply:
    I admit my situation –a school with few obviously bad teachers –could be quite anomalous.

    I’m not opposed to weeding out bad teachers. But I’m not at all sure that bad teachers are a huge factor in our educational underperformance. Do you think that they are? It seems to me that factors such as poor curricula (I’m in favor of a meaty Core Knowledge type curriculum), student misbehavior, lack of prep time, and a general pro-social, anti-academic atmosphere at many schools are more significant factors. So I’m just not that eager to initiate a witch-hunt for bad teachers. And I suspect that many of these “bad” teachers could be made better if given a better curriculum and the prep time and PD to craft great lessons. So it’s not that I’m implacably opposed to a more energetic system for weeding out bad teachers; it just seems to me to be misdirected energy.

    News this week was that France and Germany have emerged from recession –ahead of the US. And I wouldn’t characterize Toyota and Honda as companies that could learn some lessons from America about how to run a business.

    I’m not sure this answers your question exactly, but I’ve got to rescue eggplant from the broiler.

  16. “a general pro-social, anti-academic atmosphere”

    hits the nail on the head. Schools try too hard with antiquated traditions: prom, homecoming, pep assemblies, time wasters. A quick mental count in my head… I lost 5 full class periods per class last year due to shortened schedules for assemblies or other nonsense. That is a week of instruction. Show me evidence that any of these antiquated traditions have a significant and positive impact on student learning.

  17. Being the Education Emperor’s self-appointed fashion critic does have some fun perqs not the least of which is watching those who exert themselves mightily to find something good to say about the public education system determinedly, and almost comedically, ignore some of my unanswerable observations about the public education system.

  18. Swede said:

    “If the free market works to filter out bad employees and businesses all over the U.S., why would it not work for education?”

    Does it?

    In light of the financial mess we’re in now, not to mention the automotive mess, or the S&L fiasco some years ago, I think it’s hard to say that we can blindly trust the free market.

    In large companies, the employees who do well are typically the kiss-ups and the cronies, not the competent ones.

    There are small companies in which people know who the competent employees are, and treat them appropriately. Usually, however, the arrival of an MBA and/or venture capital signals the end of that era.

  19. Yeah, actually it does.

    The automotive mess is due in no small part to government intervention which gave the union sufficient power to extract deals that bore no relationship to the value the workers brought to the job from the car makers who could fund them because they had a defacto monopoly. Monopoly’s gone, car makers are gone and pretty soon the sweet deals are gone.

    That’s the value of capitalism, that it puts a cost on organizational empire-building and if someone doesn’t come along and destroy the empire the empire will destroy the company. But move that same dynamic to the political sphere and the empire-building can go on a lot longer and do a lot more damage.

    In public education the inevitable empire-building shows up as, among other things, legions of professionals who have little to do with education and whose contribution to the task of educating children is unclear. If you’re hiring people who make no contribution to the core mission of the organization how important does that make the people are important to the core mission of the organization?

  20. “The automotive mess is due in no small part to government intervention which gave the union sufficient power to extract deals that bore no relationship to the value the workers brought to the job from the car makers who could fund them because they had a defacto monopoly.”

    The government didn’t force them to build unreliable, badly-designed cars, nor to refuse to use better technology (multi-valve engines, overhead camshafts and fuel injection, to mention just a few); they ceded the small-car market to the Japanese on their own. Nobody forced them to build monstrosities like the Pontiac Fiero, in which they discovered too late that there wasn’t enough space for an oil pan. What was their solution? A smaller oil pan, leading to overheating and fires!

    It’s probably true that the unions got their lackeys in Congress (let’s not forget Tailpipe Johnny) to lean on the management, but as you point out, the companies went along because “…[they] could fund them because they had a defacto monopoly.”

    Did they think of the future? No, and that’s bad management.

    Nor for the financial genii who got us into this mess. It wasn’t the heavy hand of government that caused AIG to take incredibly stupid risks; ditto Goldman Sachs, Bear Stearns, Merrill Lynch, Wachovia, etc., etc., etc.

    The Right Honourable Barney Frank leaned on his buddy Franklin Raines to buy worthless mortgages, true; but what did that have to do with the criminal negligence of the investment banks?

    The S&L fiasco was caused in large part because the eminent M. Danny Wall, then the regulator in charge of S&Ls and thrifts, was asleep on the job. Not content with the mess he created, he then went to Utah (I think) and repeated his performance.

    I hold no brief for the government, as my occasional posts indicate. Still, to look for clear blacks and whites is to ignore reality; we live in a world of grays.

    For what it’s worth, I too think that the public school system shows government at close to its worst.

    That does not mean, however, that the free market works all the time. See Shaw’s “Apple Cart” and consider whether “Breakages, Ltd.” is pure fiction.

  21. Oh no, the free market does work all the time and as sort of backhanded proof I offer the labored misrepresentations of those who are upset at the concept of the free market. As more direct proof I’ll offer evidence that you don’t even have to be human to engage in mutually beneficial exchanges of considerations of value, i.e. free market capitalism – http://tinyurl.com/3ckdyz

    As further proof of the free market working, there are the consequences of interfering with it.

    The auto companies did respond successfully to the Japanese invasion, they just didn’t respond successfully to the *second* Japanese invasion.

    There are a whole bunch of car models, some which still exist and some which have passed into history, that were part of that response. The Nova, Comet, Fairlane, Dart and a bunch of other models that were the successful response to the initial Japanese/German automotive invasion. But to a monopolist competition is tiring and unnecessary so when the Japanese and the Germans made a reappearance the American response was less enthusiastic and less successful. Pushing the car companies in the direction of building cars with less regard for consumer preferences then for corporate convenience were the endless demands by the UAW.

    But as it became clearer that there was no succor in government action – the best the UAW and the car companies got from that quarter was the “voluntary” import restricts – the car companies acted to preserve themselves at the expense of the UAW, their tormentor.

    That’s what led to the spin-offs of the parts divisions so that the bulk of the union workers are now in only engine and transmission manufacturing and final assembly and even they’re broken into two categories – those grandfathered under older contracts and those not. The new guys are being paid much closer to what they’re worth inasmuch as their monopoly on labor is neutralized by the absence of a monopoly by the car companies for which they work.

    Also, the existence of shades of gray doesn’t preclude black and white. The free market is no more or less voluntary then gravity since mutually beneficial exchanges of considerations of value will occur whether there’s official permission or not but like the law of gravity if you’ve got sufficient power you can, temporarily, ignore the law of gravity or the free market. Eventually though gravity always wins as does the free market.

    In fact, I believe it’s the denial of the free market that’s driving education reform which, you will note, revolves now not around setting educational standards higher via some governmental mechanism but around parental, i.e. customer choice.

  22. “But to a monopolist competition is tiring and unnecessary…”

    And who would stop a monopolist from using his muscle to crush a cheeky upstart with the temerity to think that his idea deserves to be tested fairly in the marketplace? I think we can assume that our titanic captains of industry – once they stopped laughing – would suit up and take down the upstart.

    Only a regulator can do that. You might expect an informed populace to do somewhat the same, but in many cases the upstart’s idea won’t even see the light of day, so scratch the informed populace.

    As I said earlier, nobody forced Detroit to reject multi-valve engines, unibodies, fuel-injection and the like; they did it on their own. Not to mention the ossified culture that allowed people to fail their way steadily upward.

    Of course, there are plenty of examples outside Detroit. Look at Bob Nardelli; he was booted out of Home Depot in disgrace, and what was his severance? A mere $200,000,000.

    What about the financial excesses of the Wall Street investment banks? The idiocy of people like Scholes of LTCM, assuming that they could model the behaviour of people using randomness, is unbelievable unless you add an incredible amount arrogance.

    Where was the free market when Russia defaulted on its obligations and LTCM almost brought down the world’s financial system?

    Where was the free market when the S&Ls went bust under Bush I?

    None of this should be construed as a claim that government is always good. I’ve seen at close quarters the damage that government workers – those arrogant, self-righteous, overpaid, dumb, underworked whiners – can do.

    But that’s not to say the free market always works. It doesn’t.