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Good teachers really do make a difference

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Twin studies have shown that genetic factors can account for as much as 82 percent of the variability in children’s reading skills. But while genes might set the bar for reading potential, a new study published April 23 in Science shows that teachers play a leading role in helping kids reach it.

"When children receive more effective instruction, they will tend to develop at their optimal trajectory," said study lead author Jeanette Taylor in a prepared statement. "When instruction is less effective, then children’s learning potential is not optimized and genetic differences are left unrealized."

Taylor and colleagues from Florida State University in Tallahassee studied 280 identical and 526 fraternal twin pairs in the first and second grades in a diverse sample of Florida schools. Using the Oral Reading Fluency test as a measure of reading skill, the researchers determined how much of the variability in reading achievement was due to genetic factors. The twins’ classmates’ Oral Reading Fluency test scores were used to measure teacher quality—if test scores improved across the class, the gain was attributed to a high-quality teacher.

The researchers found that good instruction promoted stronger reading development. Without it, children were less likely to reach the potential conferred by their genes. "When teacher quality is very low, genetic variance is constricted, whereas, when teacher quality is very high, genetic variance blooms," they report. While teacher quality appears to be an important contributor, other classroom factors, such as classmates and resources, might also influence reading ability, the researchers noted.

With teacher quality gaining increasing attention in U.S. political circles, the study highlights the potential for education to moderate the genetic effects on early reading. "Putting high-quality teachers in the classroom will not eliminate variability among students nor guarantee equally high achievement from all children, but ignoring teachers as a salient contributor to the classroom environment represents a missed opportunity to promote children’s potential in school and their success in life," the researchers concluded.

Image: iStockphoto/Creativestock


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  1. 1. hawkeye 12:17 am 04/23/2010

    What garbage…… this supposed to be a scientific journal article? Talk about oversimplification, not to mention pseudoscience.

    Let’s see; genetics 82% (if you believe the so-called study), teacher quality (certainly, but how do you measure it?), then there’s community values (as in black kids told by peers that doing well in school is "acting white"), and quality of parents, who range from good to uninvolved to incompetent to downright crazy. And of course differences in socioeconomic status, leading to differences in opportunities and differences in nutrition and health care. Add to that environmental differences (those kids who nibbled lead-based paint as infants, and those who lived down the road from that battery manufacturer are not going to learn as well as those who didn’t). And on and on and on.

    I have family members who are teachers in affluent communities, teaching advanced-placement courses. Their students have done extremely well over the years, and they are considered "brilliant" teachers. But they are the first to tell me that the results they have obtained would be impossible in our impoverished inner city schools.

    The fact of the matter is that there are so many factors involved, in such complex interactions, that it is impossible to look at just one or two and arrive at any meaningful conclusion. Those multiple factors can be teased out and studied, but no one yet has committed the resources to do so.

    So why hasn’t anyone done a proper job of studying this problem? I don’t know, but I have some suspicions. As in the recently vetoed "reform legislation" in Florida, proposed solutions involved punitive treatment of teachers, further school budget cuts to fund standardized tests, and increased pay for private schools. This was rammed through the legislature by the republicans, as usual.

    The only reasonable explanation is that this is just another gambit in the looneytune right’s longstanding campaign to destroy public education.

    If we were really serious about quality in public education, we would fund it adequately, maintain reasonable class sizes, and pay teachers at least as much as we pay lawyers, engineers and similar professionals. Until that day, as they say on the streets, "money talks and BS walks".

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  2. 2. Archimedes 6:01 am 04/23/2010

    The USA is increasingly becoming more Orwellian, Authoritarian, and Machiavellian. This is inclusive of our educational system. The same has resulted in a new "Dark Ages" within our educational system which has rejected reason, the uniqueness of the individual, and those traditional ethical values upon which Western Civilization was based.

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  3. 3. tharriss 8:41 am 04/23/2010

    Sorry, that this doesn’t relate specifically to the article, but it is just something that I never see anyone addressing.

    What I’m curious about is why isn’t there a required class each year of high school in how to reason and in evaluating debates.

    Something that focuses on teaching children to dissect opposing arguments and break them down to find which are logically and factually more valid.

    It would be great to help our children look at all the data from our information age with the skills to better decipher truth from fiction and sound reasoning from the normal garbage that gets routinely accepted.

    We focus too much on making sure kids have a narrow scope of knowledge… this much geography, and that much history, etc…. if we teach them to reason and to be able to discern a strong argument from a weak one, they’ll be much better able to think for themselves and gather knowledge as they head out into the world.

    It is beyond me why such a crucial skill is left entirely out of the current curriculum as an official subject (although some good teachers try to wedge these skills into their classes as much as possible). It is further beyond me that more parents don’t ask about it, and that as far as I’ve seen no one is talking about it.

    Why aren’t their scientific studies on this…. I mean this article is interesting, but I’d rather see someone studying the effectiveness of a focus on teaching kids to think and reason and discern a good argument from a bad one, verses the current approach of hoping kids soak this up on the side.

    Let’s get some trials going and some research done and have some ammunition to begin changing the system into something that turns out more effective thinkers with better judgement.

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  4. 4. galaxy_man 9:57 am 04/23/2010

    Many schools measure their competency at critical thinking skills training by, as mentioned above, the standardized test. There are two funadamental flaws with this approach; first, the assumption that a standard can be placed on the learning abilities of any age group, and second, that any one test can adequately measure the development of that group. I can’t explain why logic by itself doesn’t receive attention in schools except with the conjecture that it is deemed ‘too difficult’ a subject for the majority of those attending. Critical thinking skills are limited to technical classes like physics or higher level math.

    Rhetoric, to which I assume you’re also referring, is one of the classical liberal arts. American culture has deemed the liberal arts to be useless tartuffery as far as education is concerned, mostly because they do not direct impart job related skills. The American education system is hopelessly utilitarian in function. I’m still depressed about this.

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  5. 5. tharriss 10:56 am 04/23/2010

    I’m just amazed that no educators have put together a curriculum for high school level logic/reasoning/rhetoric classes, and that there is no current discusson at any level about implementing it.

    How can they find time to teach abstinence in school, but not thinking?

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  6. 6. Bonniwell 3:05 pm 04/23/2010

    What some of you don’t seem to understand is that teachers have no control over the curriculum. We are forced to follow state and federal mandates. Standardized test data are the only "product" of public schools that seem to matter anymore.

    I would love to teach logic and literature and all those higher level thinking skills, but the idiot politicians who set the mandates only care about test results and making money for the companies that produce testing materials. Even kindergarten and first grade teachers now spend so much time with constant, redundant monitoring of phonics skills, that there’s no time to acutally read much of anything.

    If you have complaints about what teachers are presenting in class, go yell to your local school districts and politicians. When teachers complain, we are accused of being lazy for not falling in line with govenment mandates.

    The sad thing is, so many good teachers have left in disgust, and so few well-educated people are now choosing to teach, it will be very hard to find qualified people to do the job if and when the country finally wakes up tp the hatchet job the republicans (and democrats are continiuing) have done on public schooling.

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  7. 7. slashd 12:38 am 04/25/2010


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  8. 8. blindboy 2:40 am 04/25/2010

    Returning to the original point, it is impossible to quantify the effects of an individual teacher in any statistically valid way. There are just too many variables. Having sat through numerous meetings endlessly analysing results in statistically meaningless ways my current belief is that there are lies, damned lies, statistics and educational statistics!

    That said however, I am prepared to assert that good teachers do make a difference. There are numerous theories about how to become one, some better than others. If you are disinclined to work your way through them let me suggest, enthusiasm, energy, positive emotions and a strong focus on the immediate objectives of the lesson.

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  9. 9. hunterzoe 9:43 am 04/26/2010

    I agree that until our legislature and the public demand that smaller class sizes be the norm for k-12 education, there can be no serious discussion of improving education. Even good teachers will struggle to meet the needs of 30 or more children in a classroom whose abilities range from special needs, to gifted. From what I have seen from time spent in these classes, no child is having their needs met adequately. The special needs students have no aides and are not getting the extra help they need; the kids in the middle are allowed to slide along without encouragement to do more; the gifted are not challenged and end up bored; any child with behavioral challenges ends up spending alot of time out of class – in the hall, in the office, in detention and even suspension. It is a waste of potential on all counts. Imagine what a good teacher could accomplish with more time for each student.

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  10. 10. Skrashen 3:32 pm 04/26/2010

    The Florida State twin study shows that when genetics is controlled, teaching does count. BUT: (1) It counts on a test of reading aloud, pronouncing a text, not necessarily understanding it. Direct teaching does not have a noticeable impact on tests of reading comprehension (See eg Garan, 2001, in the Phi Delta Kappan).
    (2) Teaching may not count very much: A similar twin study found that instruction (teacher effects) accounted for only 8% of the variability in reading tests, also heavily dependent on decoding (pronouncing) (Byrne et al, J of Ed Psych, 2010).
    (3) Our research shows that access to reading material (libraries) counts a lot on tests of reading comprehension, about as much as the effect of poverty. D. Achterman found the same thing:
    (4) Our research shows that when you control for poverty and access to books, teaching of reading has a negative effect.
    A short report on some of our findings will appear in the California School Library Journal, in the next issue. I will be happy to send copies. Write me at
    Stephen Krashen

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  11. 11. blindboy 8:09 pm 04/26/2010

    I don’t have any problem with that Stephen but if the claim in the article is correct "Twin studies have shown that genetic factors can account for as much as 82 percent of the variability in children’s reading skills. "……..then at 8% of the available 18% teaching is still significant in at least some aspects of reading. I will email you to get a copy of your research thanks for the offer.

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  12. 12. Dede 9:10 am 04/27/2010

    OK…isn’t that common sense??? A good teacher optimizes all learning! The key here is not the money…good teachers are ususally the ones doing it with passion – not for the money. Yes, they deserve to be paid…but throwing money at a bad teacher does not improve their teaching skills.

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  13. 13. judynz 1:24 am 05/1/2010

    Good Teachers do make a huge difference. Those Teachers include parents, siblings, relatives, neighbour etc. That because learning has NOTHING to do with genes. We are taught we are intelligent beings & the understanding that this means thought process. Thoughts [words} are just that & are nothing until injected with an emotion…then one word can have, take many meanings ,inferences. Children thrive on attention & wither without it. What happened in their day even (whatever their THEN understanding of the subject) can influence (coupled with an interested teacher (some listed above) a direction that could catch their fancy. Most teachers are lousy because they simply teach by rote & children cannot be fooled. The teacher may be an expert on a subject or creating an orderly class but cannot generate enthusiasm. Despite what you may be taught to believe, genes change as individuals change.

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  14. 14. judynz 1:29 am 05/1/2010

    I have my suspicions also. We study every aspect of everything else on & within our earth (even if we get BS reports) we come across
    but we sure as heck dont want humans knowing about themselves & the very real strengths we possess.

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  15. 15. judynz 1:34 am 05/1/2010

    What!!! & have our children actually learn how to find out answers for themselves!!! Oh goodness me they might realize their kings have no clothes.

    Also digressing…have you looked at some of the videos on youtube under the heading of FREEMAN (for a start)

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