How good teachers get top marks

23rd November 2012 at 00:00
The influence of teaching quality on GCSE grades can be quantified, discovers Adi Bloom

All pupils, regardless of family background, can achieve higher GCSE grades if they are taught by good teachers, new research has found.

A pupil taking eight GCSEs and taught by eight good teachers will achieve results that are higher by four-and-a-half grades than the same pupil in the same school taught by eight poor teachers, say academics from the University of Bristol.

"Anecdotes abound of the transformational effect of excellent teaching. Yet trying to quantify this is difficult," the academics say, in a paper published in the Oxford Bulletin of Economics and Statistics.

Nonetheless, they tried. Using data from 7,305 pupils and 740 teachers across England, they noted pupils' test scores, as well as their teachers' age, gender, degree score, length of tenure and pay-scale placement.

The academics controlled for pupils' own attributes, such as intelligence, motivation, imagination and ability to learn. They also took into account subject-specific ability, measured by prior test scores.

These attributes, they found, played the greatest role in determining GCSE scores. But being taught over a two-year course by a high-quality teacher (one within the top 25 per cent of teachers) rather than a low-quality teacher (within the bottom 25 per cent) also added half a GCSE grade to pupils' achievement in the relevant subject.

For example, a pupil taking eight GCSEs and taught by eight good teachers would score four-and-a-half more GCSE points - with one point equating to one grade - than the same pupil in the same school taught by eight poor teachers.

The gain became even more marked at the extreme ends of the scale. Pupils taught by a teacher in the top 5 per cent were likely to score one-and-a-half more GCSE points in the relevant subject than they would have if taught by a teacher in the bottom 5 per cent.

In other words, the academics say, "Teachers matter a great deal ... This shows the strong potential for improving educational standards by improving average teacher quality."

And, while teacher skill has less impact on test scores than pupil character, a teacher's effectiveness can influence the GCSE results of an entire class, rather than merely a single candidate.

School and teacher allocation could play a significant role in addressing social inequality, the academics add.

"Family background is not everything. The same student, bringing to bear the skills derived from her home and family, can systematically score significantly different marks in different subjects, given different teacher quality."

They conclude: "Having a good teacher, as opposed to a mediocre or poor teacher, makes a big difference. Raising average teacher quality does seem a promising direction for public policy."


Slater, H., Davies, N., Burgess, S. "Do teachers matter? Measuring the variation in teacher effectiveness in England", Oxford Bulletin of Economics and Statistics, 74(5) (2012), 629-645.


Clarke, J. and Pye, T. Right turn for Gove; wrong turn for Initial Teacher Education?



The quality of teachers' degrees makes no difference to their ability to teach, new research has found.

Education secretary Michael Gove has repeatedly said that he believes there is a link between people's first degree and their ability in the classroom.

In The Importance of Education, published in November 2010 by the Department for Education, he stated: "The best education systems in the world draw their teachers from among the top graduates."

He later announced his intention to withdraw teacher-training funding from graduates who did not have a lower second (2:2) degree. Graduates with first-class degrees were also offered significantly more funding to train for shortage subjects than would-be teachers with lower seconds.

Academics from the University of East London therefore decided to examine the evidence. Their findings were presented at the British Educational Research Association conference this autumn.

In The Importance of Education, Gove quotes extensively from the McKinsey reports, drawing on these documents as evidence for his decisions. However, the academics point out that these reports "do not locate any of their findings within any relevant academic literature; there is no bibliography; only nine incomplete references to other books and articles, and only two to policy documents".

They then conducted an analysis of student entry and exit data for a cohort of trainee teachers. They found that all students, regardless of their initial degree classification, completed their PGCE course at a similar level.

Finally, the academics examined two tables of data from the Teaching Agency website. Entitled "Why degree quality matters", these tables purported to allow would-be teachers to estimate their chance of professional success, according to their degree classification.

The first table contains aggregate data from the period 1998 to 2010. "We know, however ... that during this period grade inflation took place within the university degree classifications, rendering any conclusions from the ... data meaningless," the academics say.

In addition, there is no difference between the outcomes for trainees with first-class and upper second (2:1) degrees, amounting to 60 per cent of the cohort. There are so few trainees with third-class degrees that the outcome is statistically insignificant.

"The authors would like to make it clear that they are not saying that secondary subject teachers do not need subject knowledge, or that teachers shouldn't be good at their subject," the academics conclude.

But, they say: "There does not appear to be any evidence to suggest a link between the classification of a student teacher's first degree result, and the award of Qualified Teacher Status."

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