Thinking about class size

This morning I gave an input on BBC breakfast in relation to a campaign to reduce class sizes by Dr Helen Vickers.


Prior to my input I have pulled together some thoughts on class size and the impact on children and teachers.

Firstly three points:

  • Naturally most parents would likely advocate smaller (below 30) class sizes. Alternatively governments may instinctively, due to cost and difficulties of teacher supply automatically edge towards larger classes.
  • Teachers would probably advocate smaller classes and there are perceived norms of class sizes in primary, secondary and different subjects. For example Art, D&T  and PE may have smaller groups than say English and Mathematics whilst SEN pupils may  also be taught in smaller groups. Equally some locations such as Scotland and Norther Ireland have mandated maximum class sizes.
  • However a significant factor in increasing class size is it is not just the increased manageability of a larger class but also the workload associated with managing an extra 25-30% of pupils. So whilst managing a group size of 40 pupils may not be inconceivable the increased demands in relation to preparation, assessment, tracking and parental involvement is significant.
  • With an increasingly likely teacher recruitment crisis it may be ‘considered’ out of the governments or schools hands; class sizes may simply have to increase due to budgets and a lack of teachers. For example there is an acknowledged worldwide shortage of approximately 5 million teachers therefore it may be more about developing a nuanced understanding of class sizes and the impact on learning than specifying a particular ratio.

But what does the research say?

Inevitably the data is mixed:

One reason for this is drawing inappropriate causal associations. So far example one problem is that if a school puts lower ability pupils in smaller classes and reports the outcomes then the outcomes would illustrate that lower group sizes equates to lower attainment (given the ability and starting point of the group). So looking at group size and outcomes is not enough.

However research by Denny and Oppedisano (2013) did counterintuitively find that using a large representative sample of high school students in the United States and the United Kingdom, that students do better on mathematics tests if the classes are larger. In this study it was however acknowledged that the influence of parents as a variable is significant and as is known in the UK the investment by parents in private tutors might be masking some of the impact of class sizes!

The Education Endowment Foundation in their summary states: “overall the evidence does not show particularly large or clear effects, until class size is reduced to under 20 or even below 15.” As such reducing a class from 30 to 25 might not have a significant impact on attainment but there may be other associated benefits such as improved teacher workload and  wellbeing or improved diagnostic of pupils learning needs.

An often cited research study – Project Star in Tennessee identified however that even a temporary reduction of class size (e.g. for a number of years) resulted in long term learning gains when classes were reduced to 15 from 25 with the biggest impact upon boys from disadvantaged backgrounds. However to have an effect  of some significance the class size must be lower than 30 and other variables have to be addressed such as the quality of teaching and the nature of teaching, learning and assessment.

Interestingly a caveat that is mentioned in the EFF summary and other research indicates that reducing the class size alone is not enough as the reduction, if it is to have an effect, should be matched with an appropriate change in pedagogical strategies. Therefore teachers in countries such as China, with an average class size of approximately 55 pupils, will equally have adapted their teaching styles accordingly (hence why we should be cautious in borrowing policies and practices from other countries).

Perhaps a significant concern is if class sizes increase – who are the increased class size most likely to impact upon? From the different studies including EEF it is noted that ‘slightly larger effects are documented for the lower achievers and those from the lower socio-economic status for very young pupils.’

Equally whilst there may be some drop in attainment as class sizes increase– financially in terms of reducing class sizes the costs may be too high for limited gains in attainment. Therefore other approaches may be considered as providing more  cost effective and efficient ways to raise attainment than reducing class sizes e.g. through a focus on metacognition or feedback. There is also suggestion that in larger class sizes pupils are afforded greater autonomy and accountability for their own learning (I suspect some may not find this convincing).

Ultimately class size is just one key factor in impacting upon attainment and a more nuanced understanding of the factors involved need to be considered particularly in relation to the pupil and teachers needs.

In terms of comparisons, the Organisation for Economic Co-operation and Development (OECD) indicates that the average for lower secondary is 23 pupils with Primary pupils in most countries having a lower average than Secondary.


In the UK unusually the Primary class average is higher than Secondary at approximately 25. It has to be remembered that these are reported averages and are not necessarily actual ratios (as typically it is the number of pupils divided by the FTE of teachers (who may not all teach)). Also it is worth noting that the UK primary school ratio is higher than many other countries e.g. US and most of Europe, whilst the secondary ratio is one of the lowest in the world.

As indicated a more nuanced understanding is still required as within a classroom it will be the quality of teaching that will be a significant factor and the adapting of teaching to the environment and the effective use of resources, including additional support teachers that will ultimately impact upon the learning.

Whilst the research is unclear as to what the optimum class size should be, given the complex number of variables associated with learning there are two factors that will remain pertinent:

Firstly class size is an indication of expenditure by governments  (and delegated decision making to Academy Chains, MATs and Free Schools) on their teaching workforce. This would also be related to teachers salaries, the amount of hours worked and the qualities (including the training) of the teacher. So questions such as ‘should teachers with larger classes be paid more’ are questions that are now delegated out to schools.

Secondly reducing class sizes alone will not necessarily have an impact on improved attainment – but attainment is not the only factor we should be concerned with. However where class size reductions take place they have to be matched by appropriate changes in  pedagogy in order to reap the benefits.

Without doubt however, an increasing worldwide demand for teachers combined with a ‘recruitment crisis’ and growth in the population is going to increase pressure on class sizes for at least the next 10 years!

Design and (or) Technlogy 2.0

In a blog post just before Christmas (December 2016) David Barlex (along with Torben Steeg and Nick Givens) argued for the rebuilding of Design and Technology based upon the current situation where less than 30% of students now study D&T. In response to David’s proposal I would agree with the identified challenges as being:

  • A lack of agreed epistemology
  • Confusion about purpose
  • Uncertainty about the nature of good practice
  • Erroneous stakeholder perceptions

However whilst there is much that I agree with in the report I would argue that the proposed rebuilding plan is prone to failure. As such I would propose a more radical reclaiming, renaming and reframing agenda in the form of developing Design and (or) Technology 2.0.

Central to this proposal are two main points:

Firstly David’s proposal is looking to rebuild a subject in an environment that has already seen the perceived failure of Design and Technology. Rebuilding in this climate, using the identified infrastructure would see humpty dumpty put back together again only to continue to fall. As such Design and (or) Technology 2.0 will only survive and evolve in an environment that will allow it thrive. As ‘designers’ we know that the best ideas don’t always prosper – they have to adapt or be adapted to their environment. As such the recommendations on page 26 of the report are those that may have worked in the past but which I don’t believe will work in the future.

Most notably lacking in the report is the full acknowledgement for the need for continued political support. Design and Technology has both grown, thrived and then been completely neglected by various governments. It was a core, compulsory subject enjoying both government interest and resourcing but in the last eight years the subject has been abandoned and mistreated. The absolute shambles of the writing of the national curriculum by civil servants perhaps best illustrates just how badly Design and Technology has fared with recent governments.

Therefore Design and (or) Technology 2.0 has to be much more politically savvy and operate and adapt to a new form of political will.

Secondly I have suggested this isn’t a ‘rebuilding’ exercise, as this would suggest attempting to recreate something we have previously had. Instead I would propose the reclaiming, renaming and reframing of the subject in version 2.0. Hence this could be Design 2.0, Technology 2.0, Design or Technology 2.0, Design and Technology 2.0 or even more radically Design, Technology and Engineering (something I posited in a report for D&TA in 2011). Lets debate!

If we take the four challenges identified by David then it is clear that there remains a lack of agreement as to what the purpose and rationale for the subject is? A good illustration of this is by taking a look at the Design and Technology Association website where it is almost impossible to identify what the subject is or more significantly what the subject isn’t about. The reason for specifically referring to the Design and Technology association website is because in David’s report the association’s influence is clearly (and rightly) acknowledged yet I would argue the associations lack of a clear rationale and sense of purpose is clearly problematic.

Over the years the Design and Technology association has undergone several cosmetic transformations, however I would suggest that any organisation that has overseen (I am not however assigning blame) the decline on the scale that we have seen really does need to think more radically about ‘reclaiming, renaming and reframing’. Central to this is the use of ‘and’ in Design ‘and’ Technology as it remains problematic and misleading. The use of ‘and’ in Design and Technology may seem nuanced but remains significant  and I will perhaps save the discussion for another occasion,  but I believe the subject (whatever that is) and the association should consider reconceiving the identity to more accurately capture the future direction and ambition of the subject rather than the clinging to the past.

Finally there is much more I could say but I regard this response as the starting of a conversation. However the final point I want to pick up on is the notion of Initial Teacher Education in D&T. Perhaps more than any other subject Design and Technology ITE has taken the biggest hit in the last 8 years. It has been dismantled to such an extent that I don’t believe at present, specifically in the context of the UK, it has in its current form the capacity to rebuild either itself or to have the impact upon the subject that is needed. Perhaps therefore the biggest challenge (and genuine opportunity) is reconceiving a way of attracting, educating and training future teachers without the existing infrastructure. Without this being addressed there is no future for any version of the subject!

Rather than reflecting however upon any of the above in some unfortunate or negative  way I genuinely believe there is now a genuine opportunity to be optimistic. David’s blog and report have opened the door to a complex and challenging debate, one that I hope the wider community will engage with!