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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

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.