Teachers loom large in most children’s lives, and are long remembered. Class reunions often talk of the most charismatic teacher, the one whose words and helpfulness made a difference. Who could doubt that they can have an influence on children’s learning and future achievements?
Doug Detterman is one such doubter:
Education and Intelligence: Pity the Poor Teacher because Student Characteristics are more Significant than Teachers or Schools.
Douglas K. Detterman, Case Western Reserve University (USA)
The Spanish Journal of Psychology (2016), 19, e93, 1–11.
Education has not changed from the beginning of recorded history. The problem is that focus has been on schools and teachers and not students. Here is a simple thought experiment with two conditions: 1) 50 teachers are assigned by their teaching quality to randomly composed classes of 20 students, 2) 50 classes of 20 each are composed by selecting the most able students to fill each class in order and teachers are assigned randomly to classes. In condition 1, teaching ability of each teacher and in condition 2, mean ability level of students in each class is correlated with average gain over the course of instruction. Educational gain will be best predicted by student abilities (up to r = 0.95) and much less by teachers’ skill (up to r = 0.32). I argue that seemingly immutable education will not change until we fully understand students and particularly human intelligence. Over the last 50 years in developed countries, evidence has accumulated that only about 10% of school achievement can be attributed to schools and teachers while the remaining 90% is due to characteristics associated with students. Teachers account for from 1% to 7% of total variance at every level of education. For students, intelligence accounts for much of the 90% of variance associated with learning gains. This evidence is reviewed.
Have we over-rated the impact of teachers, and ignored the importance of innate ability? How can we have been so mistaken? Read on.
At least in the United States and probably much of the rest of the world, teachers are blamed or praised for the academic achievement of the students they teach. Reading some educational research it is easy to get the idea that teachers are entirely responsible for the success of educational outcomes. I argue that this idea is badly mistaken. Teachers are responsible for a relatively small portion of the total variance in students’ educational outcomes. This has been known for at least 50 years. There is substantial research showing this but it has been largely ignored by educators. I further argue that the majority of the variance in educational outcomes is associated with students, probably as much as 90% in developed economies. A substantial portion of this 90%, somewhere between 50% and 80% is due to differences in general cognitive ability or intelligence. Most importantly, as long as educational research fails to focus on students’ characteristics we will never understand education or be able to improve it.
Doug Detterman is a noble toiler in the field of intelligence, and has very probably read more papers on intelligence than anyone else in the world. He notes that the importance of student ability was known by Chinese administrators in 200 BC, and by Europeans in 1698.
The main reason people seem to ignore the research is that they concentrate on the things they think they can change easily and ignore the things they think are unchangeable.
Despite some experiments, the basics of teaching have not changed very much: the teacher presents stuff on a blackboard/projector screen which the students have to learn by looking at the pages of a book/screen, and then writing answers on a page/screen. By now you might have expected all lessons to have been taught by some computer driven correspondence tutorials, cheaply delivered remotely. There is some of that, but not as much as dreamed of decades ago.
Detterman reviews Coleman et al. (1966) and Jencks et al. (1972) which first brought to attention that 10% to 20% of variance in student achievement was due to schools and 80% to 90% due to students.He then look at more recent reviews of the same issue.
Gamoran and Long (2006) reviewed the 40 years of research following the Coleman report but also included data from developing countries. They found that for countries with an average per capita income above \$16,000 the general findings of the Coleman report held up well. Schools accounted for a small portion of the variance. But for countries with lower per capita incomes the proportion of variance accounted for by schools is larger. Heyneman and Loxley (1983) had earlier found that the proportion of variance accounted for by poorer countries was related to the countries per capita income. This became known as the Heyneman-Loxley effect. A recent study by Baker, Goesling, and LeTendre (2002) suggests that the increased availability of schooling in poorer countries has decreased the Heyneman-Loxley effect so that these countries are showing school effects consistent with or smaller than those in the Coleman report.
The largest effect of schooling in the developing world is 40% of variance, and that includes “schooling” where children attend school inconsistently, and staff likewise.
After being destroyed during the Second World War, Warsaw came under control of a Communist government which allocated residents randomly to the reconstructed city, to eliminate cognitive differences by avoiding social segregation. The redistribution was close to random, so they expected that the Raven’s Matrices scores would not correlate with parental class and education, since the old class neighbourhoods had been broken up, and everyone attended the schools to which they had randomly been assigned. The authorities assumed that the correlation between student intelligence and the social class index of the home would be 0.0 but in fact it was R2= 0.97, almost perfect. The difference due to different schools was 2.1%. In summary, in this Communist heaven student variance accounted for 98% of the outcome.
Angoff and Johnson (1990) showed that the type of college or university attended by undergraduates accounted for 7% of the variance in GRE Math scores. Fascinatingly, a full 35% of students did not take up the offer from the most selective college they were admitted to, instead choosing to go to a less selective college. Their subsequent achievements were better predicted by the average SAT score of the college they turned down than the average SAT scores of the college they actually attended, the place where they received their teaching. Remember the Alma Mater you could have attended.
Twins attending the same classroom are about 8% more concordant than those with different teachers, which is roughly in line with the usual school effect of 10%.
Detterman’s paper continues with a review of other more recent studies. A good summary is shown below.
Here is a summary of the characteristics of students which predict good scholastic outcomes.
Given all that, why bother to chose a good school? Finding somewhere safe, friendly, and close to home could be important. Even if the particular school is not going to make a big scholastic difference, it can make a difference to satisfaction, belonging, and happiness. That is worth searching for.
Detterman is at pains to point out that these findings shouldn’t be taken as showing that teachers don’t matter.
Teachers should be appreciated for the difficult task they face. But no matter how good they are, they will not be able to revolutionize education or make geniuses out of every child. They do not have control over the variables that are responsible for most of the variance in educational outcome. It will do no good to lay the entire burden of reforming education on teachers as some educators have done.
Once we understand the complete infrastructure of intelligence, we will have a good start on under-standing what can and cannot be done to improve education. Without fully understanding intelligence, there will continue to be more ineffective and ill-conceived attempts to “reform” education and more blaming teachers for what is not their fault.
Teachers matter, because getting every advantage in education matters. However, a better understanding of the characteristics of the children teachers have to educate would result in teachers being more fairly evaluated.