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Expert opinion from IOE, UCL's Faculty of Education and Society


Class size and teaching: width and quality both matter

By Blog Editor, IOE Digital, on 3 February 2017

Peter Blatchford
David Aaronovitch is a good journalist and there is much to admire in an article he wrote for the Times newspaper last week (‘Teachers must get out of their ideological rut’, January 26, 2017). I suspect however that he has never taught a class of children. The line he takes – following the well publicised view of the head of OECD educational policy Andeas Schleicher – is that class size doesn’t matter. David remembers the words of his grandmother: ’feel the quality not the width’.
With my colleague Tony Russell, I am working my way through the carefully collected views of hundreds of primary school teachers, headteachers, Teaching Assistants and pupils, along with careful classroom observations and case studies (part of a large scale study we conducted at UCL Institute of Education), and what stands out are the many ways that class size does indeed matter. We have found that having fewer children in the class tends to mean more individual attention, a more active role for pupils in class, better relationships between pupils, easier classroom management, more individualisation for (more…)

Class size does make a difference – but 30 is not a magic number

By Blog Editor, IOE Digital, on 20 January 2016

Peter Blatchford
Here we go again. The arguments over class size are with us once more. Now there are worries about ‘supersized classes’ for young children in school, the result of pressure on school places and the current fragmented state of local educational planning.
Large classes are a recurring worry, especially when experienced by the youngest children in school.  Worries about this problem led the last Labour Government to introduce a legal cap of 30 on class sizes in England. Last year there was a debate in Parliament about perceived breaches of this rule by the then coalition Government, and now the problem is receiving coverage again. The concern is that the 30 maximum protection is being relaxed and this will have a negative impact on children’s education.
The educational issue here is whether there is a threshold beyond which class sizes (more…)

Moving on from the class size debate: a new project with a practical purpose

By Blog Editor, IOE Digital, on 17 February 2015

Peter Blatchford
The head of the OECD PISA surveys, Andreas Schleicher, has been called the most powerful man in education. On  the BBC website this month he described 7 big myths about top-performing school systems. Myth number 4 in Schleicher’s list is that small classes raise standards. He argues that “everywhere, teachers, parents and policy makers favour small classes as the key to better and more personalised education.” In contrast, he argues, high performing education systems invest in better teachers and high performing countries (many in East Asia) have large classes – so the size of a school class can’t be important.
Far from being a myth, however, my sense is that the view that class size is unimportant is in fact becoming more and more accepted by many (more…)

Addressing the bigger picture on teaching assistant interventions

By Blog Editor, IOE Digital, on 12 February 2014

Peter Blatchford
It is good to hear the positive results from new studies, funded by the Education Endowment Foundation, showing that interventions carried out by teaching assistants (TAs) with small groups helped improve children’s results in the 3Rs. In fact these results are consistent with earlier research, going back many years, which evaluated the use of TAs for specific interactions, usually in literacy.
These findings are welcome given the troubling results from the large scale Deployment and Impact of Support Staff (DISS) study, which I directed. We found clear evidence from a sophisticated longitudinal programme involving more than 8000 pupils that the more support pupils received from TAs over the school year the less progress they made. This was the case even when we controlled for ‘pupil factors’ such as children’s prior attainment and their level of special educational need (SEN).
I have often been asked how we can reconcile the two sets of seemingly contradictory results ­– i.e. the negative findings from DISS and the positive ones from specific interventions.
I think the explanation is clear. While the intervention studies relate to specific outcomes from a targeted programme in which TAs have been trained for the job, the DISS study was concerned with how TAs were used on a daily basis across the whole curriculum and school day.
It is no surprise that TAs, when appropriately trained, can produce positive effects, but the DISS study was also clear that for the most part TAs are not used in this way. We found that TAs were typically used in an informal remedial role with low attaining pupils and pupils with special educational needs. This support was an alternative to teacher input, not additional to it, and the pupils supported by TAs missed out on interactions with their teachers.
We also found that TAs were often under-prepared for their role – often going into lessons ‘blind’ – and had received little guidance or training. In more recent studies, my colleagues Rob Webster and Tony Russell and I have found that this deployment of TAs is still common. The problem, then, is not TAs as such, but ways in which TAs are used in schools.
Although the EEF funded research is welcome, there are a few well known problems with ‘pull-out’ interventions that need to be carefully considered when TAs are used to carry them out. If, as is the case in the EEF studies, interventions are assessed in terms of specific academic outcomes related to the literacy or numeracy intervention, they can be found to successful. But in our studies we have found that pupils are often withdrawn from the classroom for interventions and as a result become detached from the teacher, the classroom, their classmates and the curriculum. One therefore needs to account for the lost and disrupted coverage as well as the gains during the intervention.
A connected point concerns the extent to which what is learned during the intervention is connected back to the pupils’ broader experiences of the curriculum. We have found that interventions are often quite separate from classroom activities and there is relatively little communication or feedback between the TA and teacher afterwards. This meant it was often left to the pupils themselves to make any links with their mainstream curriculum coverage. Given that supported pupils were usually those with the most difficulties this was a huge challenge for them. The integration of the specific intervention and mainstream curriculum coverage is therefore vital.
But the main problem is that training TAs for specific interventions does not on its own provide an answer to the ineffective way in which they have been deployed in schools. Schools need to fundamentally rethink the way they use TAs on an everyday basis. Otherwise, their enormous potential will not be fully realised.
Our key message is this: TAs should be used to add value to teachers not replace them. Our book ‘Maximising the Impact of Teaching Assistants’ sets out strategies for schools and classroom and highlights three areas for development:.

  • We need to rethink the deployment of TAs so they are not given primary responsibility for pupils in most need. For instance, rotating groups can allow teachers to spend more time with such pupils.
  • We need to rethink the preparedness of TAs (and teachers) so they have more time to communicate and have more professional development, especially for pupils with SEN.
  • And we need to work on the way TAs talk to pupils, for example developing effective styles of questioning in support of pupil independent learning.

All of these are a challenge and all involve tough decisions, but we have found in our work with schools that huge progress is being made, and this contributes to school improvement more broadly.

Should we raise class sizes and reduce the number of Teaching Assistants?

By Blog Editor, IOE Digital, on 30 May 2013

Peter Blatchford

Ask any teacher about whether class size matters and the chances are they will say that of course, a smaller class allows for better teaching and learning. Ask any teacher whether having a teaching assistant (TA) in the classroom is beneficial and it’s highly likely they will say they are a great help.

These points seem common sense and certainly correspond to the findings of the IOE’s large scale surveys of teachers’ views. Yet, recently the Think Tank ‘Reform’ has argued that class size and TAs are not important and in the case of the former can be raised without harm and in the case of the latter can be reduced in number. This conclusion is similar to that in several high profile and widely cited reports from OECD, McKinsey, Gratton Institute and Brookings. How do we reconcile these two different perspectives – the practitioner and policy perspectives? Are teachers wrong, as some commentators imply?

To address this question we need to examine the evidence on the relationships between class size and pupil performance, and TAs and pupil performance.

To take class size first: it is striking how much recent reports base their conclusions on three sources of data: cross country comparisons, meta analyses and econometric analysis. All of these, I believe, only offer a partial view and are therefore flawed as evidence of a causal role for class size.

Results from international assessments such as the Program of International Student Assessment (PISA) show that students in the East Asia do very well and also have relatively large classes, and it is often therefore concluded that class size is not important to academic achievement. But the flaw in this argument is not considering the reasons why high performing education systems in places like Hong Kong do well, including high levels of parental support, cultural factors that favour education and the prevalence of private tutoring.

Meta analyses are based on a large scale statistical analysis of multiple studies related to the effects of class size. The conclusions have generally been that class size does not have a large influence on student learning. Yet often these analyses include studies of varying quality, age of pupil, research design, etc.

The same problem exists with econometric analyses – studies by economists who often take measures of class size, or more usually pupil teacher ratios, and develop statistical models of effects that take little account of what actually happens in school.

Interestingly these sources of data are also all secondary analyses, that is, they typically use data collected by other people. In contrast, evidence from two dedicated studies of class size – the Student/Teacher Achievement Ratio (STAR) experimental project from Tennessee and the Class Size and Pupil Adult Ratio (CSPAR) study, which I directed here at the IOE, arrive at similar conclusions: class size does matter for the younger pupils in school and small classes are particularly beneficial for the more disadvantaged and initially lower attaining pupils.

A limitation of the research examined so far is that it is all restricted to the relationships between class size and academic performance. There has been less research on class size and other aspects of classroom life, such as teaching approaches, teacher-pupil interactions and pupil behaviour. The research we have suggests that class size does affect the amount of individual attention pupils receive, and their engagement and active involvement in class. At the IOE we found in a recent study that lower attaining secondary pupils were more likely to be off task in larger classes, when compared to middle and high attaining pupils[1] Intriguingly, in several countries in Asia, including Hong Kong and Shanghai, class size reduction initiatives have been introduced – not so much to affect educational attainment (after all these countries perform very well in the PISA surveys) but to help teachers bring about higher order thinking and collaborative learning experiences.

And for me this helps explain the disparity between the views of teachers and policy commentators: when thinking about the effects of class size, teachers have in mind a broader and less easily measured set of qualities than simply scores on an achievement test. If teaching were simply about delivering a lecture then ‘Reform’ and others like them would have a strong case. But as all teachers know, teaching is not simply about presenting information.

And what about TAs? Interestingly, the research evidence on which most people draw seems to be the IOE’s Deployment and Impact of Support Staff (DISS) project in which we found convincing evidence that pupils with more support from a TA made less progress at school compared to similar children who has less support. It is therefore quite understandable that some have concluded that investment in TAs, e.g. through the Pupil Premium, is not a good use of money. But what’s important here, is how one interprets the results; in a recent book[2] my colleagues and I argue that the most likely explanation for these results is the way that TAs are used in schools and prepared for their work. Put simply: TAs are not used to the best advantage. Often TAs, with little preparation or training, are assigned a one-to-one remedial role with low attaining pupils or those with special educational needs (SEN). We suggest that this is misguided and helps explain the negative impact on these pupils. Also in another recent book we show, on the basis of a two year long action research project, how schools can fundamentally rethink the way they use TAs, so that they add value to teachers rather than replace them in the case of the most disadvantaged pupils[3].

One of the problems with the debates over class size and TAs is the way that it is presented as a binary choice: either invest in class sizes or in teaching. But the point is these are not mutually exclusive. I suspect we all agree that the quality of teaching is vital, but smaller classes and TAs can help teachers provide a more effective education for pupils. This will not happen automatically, but requires careful attention in schools in order to make the most of the opportunities that smaller classes and TAs offer.

So my conclusion is clear: raising class sizes and reducing the number of TAs are very bad ideas!

Peter Blatchford is Professor of Psychology and Education at the Institute of Education, University of London.

For more on the class size topic see: Blatchford, P. (2012) Class size: is small better? In Adey, P and Dillon, J. (Eds) Bad Education: Debunking Myths in Education. Open University Press: Maidenhead, UK –


For more on Teaching Assistants see: www.schoolsupportstaff.net


1 Blatchford, P., Bassett, P., and Brown, P. (2011) Examining the effect of class size on classroom engagement and teacher-pupil interaction: differences in relation to prior pupil attainment and primary vs. secondary schools, Learning and Instruction, 21, 715-730


2 Blatchford, P., Russell, A., and Webster, R. (2012) Reassessing the Impact of Teaching Assistants: How Research Challenges Practice and Policy. Abingdon, Oxon, UK: Routledge


3 Russell, A., Webster, R. and Blatchford, P. (in press, 2013) Maximising the impact of teaching assistants: guidance for school leaders and teachers. Routledge 










Worlds apart? How pupils with special needs lead a life away from their teachers and classmates

By Blog Editor, IOE Digital, on 8 February 2013

Rob Webster and Peter Blatchford
This week the government’s long-awaited Children and Families Bill was presented to Parliament for its first reading. The Bill – which will prompt the biggest shake up of special educational needs (SEN) in 30 years – confirms one centrepiece proposal, heavily-trailed over the last 12 months: the replacement of statements of SEN with Education and Health Care Plans (EHCPs).
Statements are awarded to pupils with the highest level of SEN; they set out a pupil’s needs and the provision that he or she should receive to meet them.
These proposals follow ministers’ views that the current SEN system is unfit for purpose. But beyond parents’ genuine concerns about the statementing process, surprisingly little is known about the day-to-day teaching and support that pupils experience once a statement is put in place. Without such information, is the call for reform premature?
Findings from our Making a Statement (MaSt) project fill this gap and raise important points for policymakers to consider. Over 2011/12, we carried out minute-by-minute observations on 48 pupils in Year 5 who had statements for moderate learning difficulties or behavioural, emotional and social difficulties, and interviewed 200 school staff and parents.
The results show that the educational experiences of pupils with statements is characterised by a high degree of separation. Compared to average-attaining pupils, they spent over a quarter of their week away from their class, teacher and peers.
A clear point to emerge from the MaSt study was the almost constant accompanying presence of a teaching assistant (TA) in the locations – both in and away from the classroom –where pupils worked. Compared to average attaining pupils, we found that pupils with statements spent less time in whole class teaching with teachers, and were more than three times more likely to interact with TAs than teachers.
In many cases TAs also put together alternative curricula and prepared intervention programmes. They also had the main responsibility for verbally differentiating teachers’ tasks, often in the moment, having had little or no opportunity before lessons to meet or prepare with the teacher.
Teachers, on the other hand, rarely had as high a level of involvement in planning and teaching statemented pupils as TAs, or provided the extra level of differentiation these pupils needed. This is very likely to be connected to the gap in knowledge teachers especially had in knowing how to meet the needs of the particular statemented pupil in their class.
As a result of current arrangements, we found that whilst the support provided (largely by TAs) was clearly well intentioned, it seemed insufficient to close the attainment gap.
Not only did pupils with statements spent less time in whole class teaching with the teacher, but they also had almost half as many interactions with their classmates compared to other pupils. This, we argue, is likely to adversely affect their social development.
Spending a week at a time observing at close quarters, and discussion with practitioners and parents/carers, brought home how schools are making every effort to attend to the needs of pupils with statements amid a period of intense flux and uncertainty in schools and local authorities. However, findings from the MaSt project and our previous research – the Deployment and Impact of Support Staff (DISS) project – raise questions about the appropriateness of current arrangements.
Statements entitle pupils to a set number of hours of TA support. Yet, the DISS project found that compared to their peers, pupils who had the most support from TAs did less well academically, and this finding was especially clear for pupils with SEN.
With EHCPs replacing statements, a key message from our research is that the currency of statements should change from “hours” to “pedagogy”. We suggest EHCPs specify the pedagogical processes and strategies that will help meet carefully defined outcomes.
Crucially though, while we recommend the new SEN reforms do away with “hours”, we do not suggest they do away with TAs. Which is why, as well as thinking more inclusively about pupils with statements, schools and teachers also need to rethink the role of TAs. Our new book, Maximising the Impact of TAs provides guidance on this.
The Making a Statement project was an independent research project, funded by a grant from the Nuffield Foundation.
To download the MaSt project Final Report, and for more on our research, visit www.schoolsupportstaff.net

The guide on the side: realising the value of teaching assistants

By Blog Editor, IOE Digital, on 23 November 2012

Rob Webster, Peter Blatchford and Anthony Russell
What does it mean to be educated? What does an educated person look like? These worthy questions were the subjects of debate at the recent IOE-hosted, London Festival of Education, and, unsurprisingly, teachers were central to responses.
The role of the teacher in shaping young minds, developing rounded individuals, and inspiring the great and the good is long established – and no doubt responsible for motivating subsequent generations to rise to the challenge of a career in teaching.
What is less often discussed, however, is what role the second largest group of school staff – teaching assistants (TAs) – can do to support the learning and development of children and young people.
TAs are an integral part of classroom life, comprising 25% of the school workforce. Yet our earlier Deployment and Impact of Support Staff (DISS) project has shown that school leaders and teachers do not make the most of this valued resource. In fact, the more support pupils received from TAs, the less academic progress they make.
Importantly though, it is not decisions made by the TAs, but decisions made by school leaders and teachers about how TAs are used and prepared which best explain these provocative results.
Michael Barber’s popular aphorism, “The quality of an education system cannot exceed the quality of its teachers”, is a helpful reminder that it’s people that make the difference in education, but their effectiveness can be constrained by factors beyond their control. We might, then, say that the effectiveness of TAs cannot exceed the quality of their deployment and preparation.
Schools, we argue, must fundamentally rethink how they deploy and prepare TAs if they are to get the best use from them in helping pupils. But there’s a third factor.
We’ve known for years that the quality of verbal interactions between teachers and pupils is at the heart of effective teaching and learning. But little attention has been given to interactions between TAs and pupils.
Our research shows that pupils are far more likely to have active and sustained interactions with a TA than they are with a teacher, but when they do, TAs’ talk focuses far more on task completion than learning and understanding.
Given the opportunity that TAs have for quality interactions with pupils, schools should think carefully about how TAs’ talk can contribute to the broad aims of producing confident young people, able to thrive in an uncertain future.
Defining a new role for TAs – one that can add value to what teachers do – was the basis for our collaborative Effective Deployment of TAs project. We found that a particularly productive starting point for rethinking the TA role was in terms of developing pupils’ independent thinking skills; to inculcate a particular habit of mind that helps pupils to figure out what to do when they don’t know what to do.
Our research shows that problems occur when TAs find themselves in a pedagogical role for which they have not been adequately prepared. Crucially, a role as the ‘guide on the side’ is less about teaching and more about helping pupils to internalise and practise valuable skills of self-sufficiency. What’s more, these skills are transferable; TAs can reinforce them across the curriculum.
The results of our study showed that schools achieved marked and productive changes to the ways TAs were deployed and prepared, and how they interacted with pupils.
We have captured how schools achieved this in our new book, Maximising the Impact of Teaching Assistants, which presents well-informed guidance and classroom-tested strategies on how to unleash the huge potential of TAs.
If school leaders explicitly set out a vision for role and purpose of TAs, and properly prepare and support them, we believe they can make a significant contribution to the way pupils learn and achieve. Perhaps, in years to come, pupils will not only talk fondly of how teachers inspired them and gave them self-belief, but of how teaching assistants did too.
Maximising the Impact of Teaching Assistants: Guidance for school leaders and teachers, by Anthony Russell, Rob Webster and Peter Blatchford, is published on 23rd November 2012 by Routledge.
To find out about a short course on this theme at the IOE click here
For more, visit www.schoolsupportstaff.net

Let's do (school) lunch: lessons in social and emotional development can never replace the real thing

By Blog Editor, IOE Digital, on 24 July 2012

Ed Baines and Peter Blatchford
School lunchtimes have been stirring up a lot of interest. Jamie Oliver’s campaign to improve school meals has been very successful and the Children’s Food Trust has picked up the mantle to help schools improve children’s dinners with their latest survey showing year-on-year increases in uptake of school meals. All of this should help improve the health of our children and address concerns about obesity. But there is another way in which school meals and lunch times are important, and that is their social value.
School lunchtimes are often overlooked as a key time during children’s lives for socialising with peers and friends of their own choosing. In a programme of research studies we have conducted, we have found that breaktimes, and particularly lunchtimes, are a main site for meeting with friends and engaging in enjoyable activities in relative safety without the close intervention or control of an adult. In contrast, children in class are quietened and hurried along by teachers anxious to make the most of the curriculum time available. Our surveys also have shown that out of school there are reduced opportunities for socialisation and outside play – largely brought on by parental concerns about transport and stranger danger.
School lunchtimes therefore provide one of the main opportunities for free social interaction with friends and peers and – worryingly – for some it might be the only time. Despite the huge attention given to incidences of bullying, our surveys of pupil views also show that for the vast majority of children, for the large majority of the time, school lunchtimes are important times for developing relationships and social skills.
Children engage in extended conversations on topics of their own choosing, learn about small talk and share enjoyable experiences, plan activities together with friends and acquaintances and support each other when life is not so rosy, develop early forms of social capital and learn the give and take of social relationships. School lunchtimes therefore offer a wealth of social, emotional and moral opportunities – but they are overlooked as occasions for the learning of important lessons, largely because teaching does not take place and they are not part of the formal curriculum.
What is more, lunchtimes, whether we are talking about eating a meal or opportunities for outside play and social engagement, are times that the substantial majority of children in our surveys report being very happy indeed. So from the perspective of recent efforts to measure and to improve national happiness and wellbeing one could do much to try and preserve these social occasions for children.
However, our national surveys of school breaktimes, funded by the Nuffield Foundation, have made it clear that the length of school lunchtimes have been shortened over the past 20 years. The main reasons cited are worries about covering the curriculum and pupil behaviour. Secondary schools in particular seem to see lunchtimes in functional terms as times to have a break and eat, and shorten them accordingly. Many offer only 35 minutes for lunch before students are expected to head back to the classroom for another dose of instruction.
It may be that such reductions are at the expense of time for social activity and play rather than eating time. Our surveys suggest that children and adolescents are happy with the amount of time they have to eat but feel they should have more time to interact with friends and peers outside of the dining room. We worry that there is a general absence of understanding about these times, how they are organised, what takes place and their social and emotional value.
When thinking about school lunchtimes we should not forget that these times are principally social events. It may even be the case that the recently identified positive benefits associated with meal times (for example, on classroom engagement) may be as much to do with improved opportunities to socialise with friends and peers as the food and opportunity for a break.
When challenged, policy makers and schools might be excused for thinking that break and lunchtimes are disposable. They are often cited as occasions for negative behaviour and there are concerns about health and safety and taking time away from school work. It might also be argued that social and emotional skills are often taught as part of the school curriculum (through SEAL, PSHE and circle time). While these lessons are good opportunities for reflecting on and thinking about social relationships and behaviour, they are not, and can never be, replacements for the real thing.

The pupil premium: should schools invest in teaching assistants?

By Blog Editor, IOE Digital, on 17 May 2012

Peter Blatchford and Rob Webster
The government has announced plans that could change the way schools manage provision for some of the most vulnerable pupils. Both the injection of cash for pupils on free school meals via the Pupil Premium and the plan to give parents of pupils with a statement of special educational needs (SEN) control over their child’s SEN budget are part of the coalition’s drive to give schools and parents the power and resources to fund the expert support they need to progress.
Of course, the groups of pupils at whom these two funding sources are targeted are not the same, though they do overlap: the government’s own data show that pupils with a statement for SEN are twice as likely to be eligible for free school meals as their peers.
Much has been made of the devolution of power from the centre in the drive to close the attainment gap between disadvantaged pupils and their peers. Deputy Prime Minister Nick Clegg, for example, made a virtue of the freedom headteachers have to spend the £488 per child Pupil Premium. He wants to see schools innovate, then publicise the most effective strategies.
Over the last 15 years, teaching assistants (TAs) have become a central part of policy and practice in meeting the needs of lower-attaining pupils and those with SEN. Over this period, TAs have grown to comprise a quarter of the UK mainstream school workforce. The general sense is that using TAs to provide one-to-one and small group support to struggling pupils works well, and it is likely that schools will seek to extend this through the Pupil Premium. However, our research offers a word of caution.
Results first published in 2009 and described in our new book, Reassessing the Impact of Teaching Assistants: How Research Challenges Practice and Policy, raise concerns about the impact of TA support on pupils’ academic progress.
Our five-year study, the Deployment and Impact of Support Staff (DISS) project (the largest study of TAs worldwide) measured the effect of the amount of TA support on the academic progress of 8,200 pupils, while controlling for factors like prior attainment and level of SEN. Worryingly, our analyses across seven year groups found that those who received the most support from TAs consistently made less progress than similar pupils who received less TA support.
So, are we suggesting that schools and parents look elsewhere to invest their funds? Far from it. Blaming TAs would, in our view, be wrong. As other results from the DISS project show, it is the decisions made about – not by – TAs, in terms of their deployment and preparation, which are at fault.
We found that there has been a drift towards TAs becoming, in effect, the primary educators of lower-attaining pupils and those with SEN. Teachers like this arrangement because they can then teach the rest of the class, in the knowledge that the children in most need get more individual attention. But the more support pupils get from TAs, the less they get from teachers. What is more, our detailed analysis of classroom talk showed that compared to teachers, TAs’ talk to pupils tends to focus on task completion rather than developing understanding – most likely as a result of having limited opportunities to meet with teachers before lessons.
The government has not ringfenced Pupil Premium cash, but it will – via Ofsted and league tables – hold schools accountable for how it is spent. Our view – outlined in Reassessing the Impact of TAs – is that schools must undertake a fundamental rethink of the purpose and role of TAs if they are to get the best use from TAs and help disadvantaged pupils.
To this end we have been conducting a follow up study, funded by the Esmée Fairbairn Foundation, in which we have been collaborating with schools to develop and evaluate strategies for improving the use of TAs. The results of this research, which to date are extremely positive, will feature in a future blog.

Class size or teaching quality? The pendulum swings again

By Blog Editor, IOE Digital, on 27 April 2012

Peter Blatchford
The class size debate has opened up once again. The prevalent view this time seems to be that class size is unimportant. This was apparent in the media coverage of one London council leader who wanted the cap of 30 in a class for the youngest pupils to be relaxed. The thinking is that reducing class sizes is not a cost effective use of public funds and that money could be better spent, particularly on improving teaching quality.
More worryingly, more and more people are now arguing that class sizes could even rise. The judgment of teachers themselves – which we have found is overwhelmingly that teaching and learning are better in smaller classes – often gets overlooked or even denigrated as self serving.
For me, much of the commentary on this topic contains a common but flawed way of thinking about class size. No one could disagree that teachers and teaching quality are the most important ingredient in successful education. But the two biggest studies of class size effects – the STAR project from Tennessee and our own study based at the IOE – are also clear: the number of pupils in the class significantly affects young pupils’ educational progress. The mistake I think is to assume a choice has to be made, as if teaching and class size are mutually exclusive. The number of pupils in a class is an important contextual influence on the quality of teaching which takes place, and the important thing is the way that class size and teaching interconnect.
The question I think needs to get asked more is what teaching approaches work best in smaller (or larger) classes? This is a particularly pressing question in a number of countries in Asia. In Hong Kong for example, despite high performance in international comparisons of academic success, they are reducing class sizes as a matter of policy. In our extensive series of observation studies of class size effects, as part of the IOE research, we found that in smaller classes there was more individual attention and more pupil classroom engagement. But other research has also found that teachers do not always alter their style of teaching when faced with fewer pupils in the class, and could therefore benefit from help with effective strategies in small classes.
During recent visits to primary schools for a current research project on the educational supports given to pupils with special educational needs (SEN) in mainstream classes, I have been struck by one way that class size and teaching are intimately related. It is clear that teachers face an extremely difficult task when seeking to teach pupils in often large and very varied classes that sometimes include pupils with special educational needs.  
Those who argue that class size effects are unimportant seem fixated on evidence exclusively couched in terms of academic achievement test scores. But there are other features, including skills at differentiating the curriculum for pupils at very different levels, which are affected by class size but rarely get a mention, and still less studied in research.
So pitching class size against teaching is far too simplistic. They are both important. A key task for the future is to develop and evaluate effective teaching approaches when faced with different numbers of pupils in the class.