Thursday, 14 May 2020

COVID19 – Progress Report and Planning for School Reopening - ISBA Webinar

An Independent Schools Bursars Association (ISBA) webinar given by Mark Steed on Thursday 14th May 2020 updating on how Kellett School in Hong Kong is preparing for reopening the school after 15 weeks of Covid-19 closures.

The Webinar is here:

The Slides are here:

Thursday, 16 April 2020

How to attract teachers to work in your school - a COBIS Webinar

A COBIS webinar given on 16th April 2020 on teacher recruitment to international schools. The presentation looks at innovative ways of finding talent and ways in which schools can position themselves by building their recruitment brand.

The Video of the Webinar can be seen here

The PowerPoint Slides are here:

Wednesday, 1 April 2020

How to support pupil, staff and parental wellbeing when your school is closed

A Tes Webinar presented on 1st and on the 29th April 2020, drawing on the experience of Kellett School In Hong during the closures because of Covid-19


Thursday, 26 March 2020

Covid-19 - How a school is dealing with it 40 days on

Webinar presentation slide deck. ISBA Webinar 26th March 2020 outlining how Kellett School in Hong Kong has coped with an extended school closure.


Thursday, 5 March 2020

Preparing for Covid-19 Closures - Pt1: Advice for School Business Managers:

The following advice is offered to fee-charging schools (UK Independent Schools and International Schools) on how they should prepare for Covid-19 closures in light of our experience in Hong Kong.

School Site Preparations 

Schools obviously need to follow the medical advice issued in their local jurisdiction. However, schools should prepare for this this by endeavouring secure essential supplies.

In advance of this, schools would be well advised to order stocks of:
  1. masks; 
  2. hand sanitizer – install more permanent points around the school; bottles need to be available in every classroom, if supplies allow; 
  3. cleaning fluid; 
  4. "pistol-style” thermometers as these are most effective for monitoring temperature on entry to the school; 
  5. toilet roll! 
Put in place other measures and protocols: 
  1. Reduce the number of points of entry to the school site so that each point can be supervised (heat checks, hand sanitization, travel declaration etc.); 
  2. Create travel declaration forms: everyone coming onto site to make a declaration re. their travel history during the past 14/28 days and warranting that they have not knowingly come into contact with anyone who has the virus; 
  3. Arrange for more regular cleaning of the school site: - 3 or 4 times a day; This may entail limiting the use of the site; 
  4. Keep internal (non-fire) doors open to reduce the amount of physical contact that staff and students have with door handles ; 
  5. If disinfectant supplies are low, consider draining the swimming pool – swimming pools use up significant cleaning resources: the double concentration used to clean the poolside for a week can be watered down to clean the school for a month. 

Financial Preparations – “Cash is King” 

One of the challenges that faces fee-charging schools at this time is that they are likely to be sending out the Term 3 fee bills during when the school is closed for an uncertain period of time. It should be recognised that most schools have little choice but to so this for reasons explained below. Bills are never popular and this is all the more the case where there is a perception that they are being charged for a service which they are not receiving. In addition, schools are likely to be faced with requests for refunds on any extra-curricular activity (ECAs) fees, bus fees, and charges for instrumental music lessons. 
Most schools operate with limited cash reserves (usually about 3 months/ a term's fees). Schools therefore should make preparations for late or non-payment, demands for fee reductions, children being withdrawn from the School at no notice, and the cost of a proportion of associated legal disputes. Whilst robust parent-school contracts might mean that these issues are likely to be resolved in the school’s favour in time, short-term non-payment does pose a significant problem for schools. Whilst school fees make up the lion share of a school’s income, be aware that a Covid-19 closure is likely to have a significant hit on the income from term-time and holiday lettings. 
With three payment points each year, the cash-flow cycle for schools is lumpy at the the best of times. This particular crisis could not have come at a worse time of year, for, typically, the Term 3 fee round has to fund five months of teachers’ salaries (April to August), end of service gratuities (if applicable) and a portion of summer works. Because of these factors, schools need to put in place measures to shore up the school’s cash position. This is easier said than done. Schools have a much higher proportion of fixed committed expenditure than many other industries: teacher salaries typically account for 75% of a budget. In practice there is very little flexibility. 
Schools therefore need to look into ways of preserving cash by looking for payment holidays on any borrowing, increasing lines of credit with their bankers, as well as delaying any discretionary expenditure (e.g. summer works). Furthermore, requests for refunds for ECAs, bussing and Music Lessons are best managed by giving credits for the following term, rather than giving full refunds, thus preserving cash. 
From a parental perspective schools fulfil three functions: first, teaching and learning – the preparation for examinations and university entry; secondly, easy access to an extra-curricular programme; and, thirdly, childcare. The relative importance of each of these aspects varies depending on the age of the child. When schools are closed for long periods of time, as necessitated by the Covid-19 virus, schools are only able to fulfil the first of these functions. In the medium term, schools will need to decide if they are going to offer a discount or a fee freeze in order to appease or retain parents. This is likely to vary between schools and context, depending on future demand for places at the school.

Sunday, 2 February 2020

Daniel Susskind A World Without Work (2020) Summary of Key Arguments

Daniel Susskind, Economics don at Balliol Oxford, leads the reader through a persuasive well-structured argument that the automation that we are seeing today will be profoundly different from technological change in the past. The consequence of this is that we need to rethink the status of work and look to new ways to shape our society in a ‘world without work’.

The Context 

Ch.1. A History of Misplaced Anxiety 

A survey of the effect of technology on work over the past three centuries is characterised by two rival forces: a harmful substituting force which displaces human beings from performing particular tasks because the technology is faster or cheaper; and a helpful complementing force which raises demand for the work of humans to perform other tasks (e.g. the rollout of ATM machines did not replace bank tellers, but it meant that their role changed to provide customers with a better service p.26)
The helpful complementing force to date has done this in 3 ways:
  1. the Productivity Effect: machines have made displaced workers more productive at other activities; 
  2. the Bigger Pie Effect: technology has made economies and incomes around the world much bigger; 
  3. the Changing Pie Effect: technology changed how consumers spend their incomes and how producers make goods and services available.
“Up until now, in the battle between the harmful substituting force and helpful complementing force, the latter has won out and there has always been large enough demand for the work that human beings do” (p.28)

Ch.2. The Age of Labour 

“a time when successive waves of technological progress have broadly benefited rather than harmed workers.” Autor-Levy-Murnane ALM Hypothesis: Machines could readily perform the ‘routine’ tasks in a job, but would struggle with the ‘non-routine’ ones (p.39) Technological progress is neither skill-biased or unskilled-biased it was task-biased (p.40).

Ch.3. The Pragmatist Revolution and Ch,4. Underestimating Machines

Greek Poet Archilochus: ‘The fox knows many things, but the hedgehog knows one big thing.’ p.64 – “we should be wary not of one omnipotent fox, but of an army of industrious hedgehogs” p.67)
AI Purists (cognitive scientists) closely observe human beings acting intelligently and try to build machines like them. This approach and the quest for Artificial General Intelligence AGI, to date, has failed. (c.f. the omnipotent fox remains illusive)
AI Pragmatists (computer scientists) take a task that requires intelligence when performed by a human being and build a machine to perform it in a fundamentally different way – relying on advances in processing power and data storage. The quest for Artificial Narrow Intelligence ANI is proving quite fruitful (c.f. the army of industrious hedgehogs).
“The temptation is to say that because machines cannot reason like us, they will never exercise judgement; because they cannot think like us they will never exercise creativity; because they cannot feel like us, they will never be empathic. All that may be right. But it fails to recognise that machines might be able to carry out tasks that require empathy, judgement or creativity when done by a human being – but doing them in some entirely different fashion.” (p.72-73)
“We do not need to solve the mysteries of how the brain and mind operate to build machines that can outperform human beings.” (p.74)

The Threat 

5. Task Encroachment 

Technology is encroaching on all areas of work: Manual capabilities (agriculture, driverless cars, car manufacturing, construction industry, 3D printing); Cognitive capabilities (Law, Medicine, Education, Finance, Insurance, Botany, Journalism, Military – “Computational creativity”) Affective Capabilities (“affective computing”, “social robotics”)
Task encroachment will be taken up at different paces. Because
  1. “some tasks are far harder to automate than others”; 
  2. in some industries the cost of human labour is low and complexity of automation is high (e.g. cleaning, hairdressing, table-waiting); 
  3. different cultures and jurisdictions will have different attitudes and regulations. 

Ch.6. Frictional Technical Unemployment 

“There is still work to be done by human beings; the problem is that not all workers are able to reach out and take it up” (p.99).
Three reasons for this:
  1. A Skills Mismatch (work available for much more qualified or more skilful); 
  2. An Identity Mismatch (work available but doesn’t fit will self-image – not a graduate job, or a man’s job – jobless lorry drivers may not want to do “pink collar” work such as child care); 
  3. A Place Mismatch (the work available may be in a different part of the country/ world) 
There will be 3 consequences of Frictional Unemployment: the “technological overcrowding, with people packing into a residual pool of whatever work remains within their reach” (p.109):
  1. there will be downward pressure on wages; 
  2. there will be downward pressure on the quality of the work; 
  3. there will be downward pressure on the status of the work available (rich-poor, master-servant divide). 

Ch.7. Structural Technical Unemployment 

In the future the Complementing Force is likely to be much weaker: 1) The Productivity Effect – “As task encroachment continues, human capabilities will be come irrelevant . . . for more and more tasks” (p.114); 2) The Bigger-Pie Effect – “a growing demand for good may mean not more demand for the work of human beings, but merely more demand for machines” (p.116); 3) The Changing Pie Effect – for consumers, “As task encroachment continues, it becomes more and more likely that changes in demand for goods will not turn out to be a boost in demand for the work of humans, but of machines” (p.119); and for producers, “As task encroachment continues, will it not become sensible to allocate more of the complex new tasks to machines instead?” (p.121).
“It is a mistake to think that there is likely to be enough demand for them [human beings] to keep everyone in work” (p.124). 
For Susskind, at present there is an assumption that human beings are superior to machines; in future we may need to assume that we are inferior.
“Just as today, we talk about ‘horsepower’ harking back to a time when the pulling power of a draft horse was a measure that mattered, future generations may come to use the term ‘manpower’ as a similar kind of throwback, a relic of a time when human beings considered themselves so economically important that they crowned themselves as the unit of measurement” (p.130). 

Ch. 8. Technology and Inequality 

 “The largest economic pies, belonging to the most prosperous nations, are being shared out less equally in the past” (p.137) 
The longstanding relationships between traditional (33.3%) and human capital (66.6%) is changing: Traditional Capital “is everything owned by the residents and governments of a given country at a given point of time, provided that it can be traded on some market” (p.133). Human Capital is “the entire bundle of skills and talents that people build up over their lives and put to use in their work” (p.134).
Susskind identifies three trends (p.146):
  1. “human capital is less evenly distributed”; 
  2. “human capital is becoming less and less valuable relatively to traditional capital”; 
  3. “traditional capital is distributed in an extraordinarily uneven fashion”. 
“Today many people lack traditional capital, but still earn an income from the work that they do, a return on their human capital. Technological unemployment threatens to dry up this latter stream of income as well, leaving them with nothing at all” (p.149). 

The Response 

Ch.9. Education and its Limits 

“’More education’ remains our best response at the moment to the threat of technological employment."
We can do this in 3 ways:
  1. What we teach: “do not prepare people for tasks that we know that machines can already do better; or activities that we can reasonably predict will be done better by machines very soon” (p.158) N.B. “Many tasks that cannot yet be automated are found not in the best-paid roles, but in jobs like social workers, paramedics and schoolteachers.” 
  2. How we teach: non traditional blended-learning and online learning methods need to become more commonplace. 
  3. When we teach: we need to move to a world of life-long learning: “People will have to grow comfortable with moving in and out of education, repeatedly, throughout their lives. We will have to constantly re-educate ourselves” (p.160). 
“Even the best existing education systems cannot provide the literacy, numeracy and problem-solving skills that are required to help the majority of workers compete with today’s machines” (p.165). 
“Some people may cease to be of economic value: unable to put their human capital to productive use, and unable to re-educate themselves to gain other useful skills” (p.166). 
“Education will also struggle to solve the problem of structural technological unemployment. If there is not enough demand for the work that people are training to do, a world-class education will be of little help” (p.166). 

Ch. 10. The Big State 

The role for the state in the C21 world without work is to deal with the looming disparities and inequalities in society. It will do this through taxation and redistribution of income and wealth. Taxation: 
  1. 1) taxing workers who have managed to escape the harmful effects of task encroachment; 
  2. 2) taxing capital – taxing “the income that flows to owners of increasingly valuable traditional capital” (p.176); 
  3. taxing big business – this needs to be tackled at a global level. 

Redistribution: Susskind rejects the idea of Universal Basic Income (UBI) which has no strings attached. He has an excellent critique of the problems associated with membership criteria for UBI. He argues instead for a Conditional Basic Income (CBI) which requires recipients to contribute in some way (to be defined) to society. This is based on a view of ‘contributive justice’ whereby everyone feels that their fellow citizens are giving back to society. His vision is for a ‘Capital-sharing State’ and a ‘Labour-supporting State’.

Ch. 11. Big Tech 

For Susskind, Big Tech companies are here to stay for two reasons:

  1. Expensive Resources: it costs enormous amount to develop new technologies – huge amounts of data, world-leading software, and extraordinarily powerful hardware. Small firms cannot compete and talented ones just get bought out. 
  2. Network effects – networks are more rewarding the bigger they get. 
Susskind rejects the economic arguments against large monopolistic firms – most are not abusing their monopoly economically. Instead he questions their political and social influence. Here he argues for new regulatory institutions which can insist on greater transparency and ensure that liberty, democracy and social justice are not under threat.

Ch,12. Meaning and Purpose 

A world without work throws up philosophical questions about how human beings find meaning; and practical questions of how people will spend their leisure time: volunteering, unpaid work, community required activities (see Conditional Basic Income above).
 “A job is not simply a source of income but of meaning, purpose and direction in life as well” (p.215). 
In the C21 “Work is the opium of the People”. Work has meaning beyond the purely economic. “The problem is not simply how to live, but how to live well” (p.236).
Revisiting Education. Spartan King Agesilaus: ‘the purpose of education is to teach children the skills that they will use when they grow up.’ Perhaps schools should prepare young people for a world of leisure: character, virtue, life skills education.
“If free time does become a bigger part of our lives, then it is likely also to become a bigger part of the State’s role as well” (p.234) 
A world without work throws up three fundamental problems:
  1. the problem of inequality; 
  2. the problem of political power; 
  3. the problem of meaning.

This is an important book - essential reading for anyone who is interested in preparing young people for the future.

Wednesday, 22 January 2020

Tale of Two Cities: 6 Lessons Learned about Digital Transformation

Presentation given at the EdTech Conversations event (BETT Fringe) on Thursday 23rd January 2020. This presentation looks at 6 Lessons Learned about Digital Transformation from my time at JESS, Dubai and at Kellett School, Hong Kong.


Tuesday, 21 January 2020

AI in Education: Four Risks that we need to consider

The Holy Grail of EdTech is an AI-driven autonomous system that provides a personalised learning experience with minimal teacher input. This is not surprising given the potential financial rewards that such a system would bring. Education is very big business. According to IBIS Capital [Global EdTech Industry Report 2016], education was $5 trillion industry globally in 2014 and is growing at $600 billion a year. However, only 2% of it is digitised – education as an industry is a ‘late adopter’ at best. EdTech is increasingly being seen as a ripe market for investors. Three factors make it very attractive: the importance and cost of education to Governments and parents; the global teacher shortage and the unsustainability of the present model of one teacher to 20-30 students; and the abundant scope for new markets (there are currently 263m children in the world not in education). There is scope here to be the ‘Amazon of Education’ - no wonder the Venture Capitalists are turning their attention to EdTech.
However, we are not talking about the automation of the sale of books here - we are talking about the education of young people and there a range of ethical concerns which need to be addressed at an early stage.
  1. Skewed Dataset. We are still in the ‘Early Adopter’ phase of the use of Educational AI. It is at present an ‘enhancement’ of existing educational processes and therefore pioneering schools need to be at a relatively high level of digital and pedagogical sophistication to be able to deploy these systems. We need to recognise that these systems are being developed using an unrepresentative dataset which has implications for fairness and wider applicability down the line. 
  2. AI Summative Judgements. At present educational platforms are using AI to make formative judgements on individual students (based on what is likely to be a globally unrepresentative dataset) in order to tailor learning to the needs of the individual student. There is a risk down the line that we may see AI educational systems replace the present public examination system, making summative judgments that have a significant impact on life choices such as access to higher education or certain levels of employment. Furthermore, judgments might be made on wider criteria than presently deployed. For example, rather than just assessing whether or not a student has mastered a particular skill or unit of knowledge, it would be possible to assess how fast a student takes to so.
  3. Digital Divide: As AI becomes more commonplace, there is a danger of an educational ‘digital divide’ between those generally wealthy countries who can afford to deploy AI educational systems and those who do not. (c.f. There were significantly lower participation from Africa in the recent MIT project Awad et al ‘The Moral Machine Experiment’ Nature Vol 563 November 2018).
  4. Monopoly on Education. It is conceivable that, in time, there will be a few large companies, the 'Amazons of Education' if you like, who would dominate the automated-education industry. These providers would be able to control the content of what is taught (in the way that some Governments around the world do today). It would be possible, for example, for these companies to decide that the Holocaust should not be on the C20 history syllabus (as is the case in many Arab states today); or they might promote certain ideologies or lifestyle choices (vegetarianism, hetrosexuality, etc.). We should avoid a world where a minority have a monopoly on education. 
It is time to have the moral debate about AI in education

Friday, 17 January 2020

4 red flags to check for in an international school

Most international schools are highly professional, above board and are great employers – but, as with most industries, there are some cowboys out there who cut corners to make a fast buck. However, unscrupulous schools are easy to spot if teachers do their own "due diligence" and check out their potential employer. Here are my four key red flags to watch out before you sign on the dotted line…

1. 'Visa runs' 

Reputable schools will ensure that a work visa is in place before you start work – it will either be sent to you in advance or left so that it can be collected from the visa desk at airport arrivals. Sadly, this will not always be the case. Some international schools expect new staff to enter the country on a tourist visa, which they will then change to a resident work visa in due course.
A tourist visa is usually only valid for 30 or 60 days and there are per diem fines for staying beyond the allotted time. So, if the 30 or 60 days elapses before the work visa has been processed, schools expect teachers to go on "visa runs" – i.e. to leave the country and re-enter on another tourist visa. I’ve heard of cases where teachers have had to go on visa runs throughout their first year working. Although the travel costs are usually picked up by the school, there is a personal cost in time (for example, a lost weekend) and in terms of settling in and establishing a normal life (a work visa is often required to get a local bank account).
In most countries, it is illegal to work on a tourist visa and, again, there are hefty penalties for both the employer and the employee if caught. This puts the new teacher in a very vulnerable situation. One of the major reasons why schools are not able to process work visas promptly is that the school itself does not yet have all of its paperwork in place. New schools typically have to go through a long process of documentation involving several government departments before they can get the status to sponsor work visas. In their rush to meet a September opening deadline, many new schools are forced to cut corners – visa runs are a symptom.

2. Cash payments and employer shock 

The norm in international schools is for your school to pay your salary into your local bank account. However, there are times when this is not possible because you have not been able to set up a bank account because your visa paperwork is not in place. In these cases, the school has no alternative but to pay the teachers in cash, which can be hugely inconvenient for the teacher.
 In similar vein, there are many examples of it only becoming apparent at the first pay day that the de facto employer is not the school for whom you’ve been working for the past month, but some other third-party company. This happens because schools (particularly UK franchise schools) enter into partnerships with local companies who own and manage the school.

3. Accommodation anomalies 

Many international schools provide accommodation to teachers as a benefit for the first part of their term of employment. Sadly, there are many cases in which schools do not deliver the type of accommodation that was promised at interview. In some cases, flats are smaller than expected or of a lower quality; in others, they are in a totally different part of the city, necessitating a lengthy daily commute. At its worst, single staff are informed for the first time on arrival that they are required to share an apartment – or even a room.

4. Beware the scams: jobs that don’t exist 

Check that the job actually exists. There have been a number of scams in the past decade in which scammers use the names of prestigious schools to con prospective teachers. The scammers send out job offers on amazing terms but to clinch the deal, the unsuspecting candidates are required to wire a few thousand dollars to a purported travel firm so that visa papers and work permits can be processed, money which they say will be refunded once they have joined the school. Suffice to say that no reputable school requires candidates to pay costs up front in this way.

“Time spent on reconnaissance is seldom wasted” 

Moving abroad is costly and involves making personal sacrifices (resigning a good job in the UK, relocation, etc). Because of this, most teachers are so invested in their move that they have no alternative but to play along when a bad employer moves the goalposts. In practice, when things go wrong it is very difficult for a new teacher to challenge a school over its poor practice during the first months of living abroad. The choice is binary: put up, shut up and stay – or quit. All this can be avoided if teachers do their own research before committing to a particular school.

Due diligence checklist 

Contact teachers (via LinkedIn or other social media) who are working or worked recently at the school and ask them:

  1. How long did it take you to get your work visa? 
  2. Did you or any of your colleagues ever have to go on a "visa run"? 
  3. Did you or any of your colleagues ever get your salary paid in cash? 
  4. Who is your actual employer? 
  5. Who pays you each month? 
  6. Did your school accommodation align with your expectations from interview? 
  7. Are you planning on renewing your contract when it ends? If not, why not? 

Look for the kitemarks 

One way to identify the more established and reputable schools is to research the international organisations to which schools can belong. The international schools in the Headmasters' and Headmistresses' Conference (HMC), the Council of British International Schools (COBIS) and the Federation of British International Schools in Asia (FOBISIA) have extensive inspection regimes, which will ensure that a high standard of best practice is followed in the schools that bear their kitemark.

This article was published in Tes on 16/01/2019

Monday, 13 January 2020

Independent Schools as vehicles of social mobility? Digging deeper into the Statistics.

Approximately 6.5% of UK school children are currently educated in independent schools. However, this general figure masks a much more complex reality. In practice, about 3% of 5-year olds and approximately 15% of school pupils over the age of 16 attend an independent school (ISC Annual Census and Annual Report 2019, p.13). 

The use of historic data 

Critics of independent education often point to the disproportionate role that former pupils play in public life: 65% of senior judges, 57% of Members of the House of Lords, 52% of diplomats and so on (Sutton Trust Elitist Britain 2019). Yet these statistics belie the fact that many schools which are today independent schools were Direct Grant schools at the time when these senior figures were at school. Direct schools such as Manchester Grammar, Bradford Grammar, Leeds Grammar, Haberdashers’ Aske’s and Latymer Upper were all significant feeders to university, Oxbridge and into the professions. 
If we genuinely want an informed (rather than ideologically partisan) debate about the place of independent schools in our society, it would be useful to know what proportion of the leading figures educated at independent schools in the Sutton Trust’s Elitist Britain survey were themselves beneficiaries of the Direct Grant scheme. These data would give an indication of the extent to which independent schools were a vehicle for social mobility in the 1960s and 1970s, and thus inform debates about future policy. 
There is little doubt that the abolition of the Direct Grant scheme in 1976 and of its successor, the Assisted Places Scheme, in 1997 had a significant impact on the independent sector’s ability to transform lives on a large scale. There is little doubt too, that above inflation fee increases over the past thirty years have limited the number who are able to afford access to independent schools.

Independent schools as vehicles of social mobility 

And yet we know that Independent schools still have the ability to be vehicles of social mobility and to transform lives. That a third of students at Oxford University who come from low-income backgrounds and qualified for free school meals went to independent schools, is testimony to this. In the words of Professor Louise Richardson, Vice Chancellor of Oxford University: 
“The reality is that independent schools are identifying these smart, poor kids. They are bringing them in, giving them scholarships and educating them, and then they apply to us, and we take them.” (‘Oxford’s admission problem is because state schools fail to push their brightest pupils’ vice chancellor suggests’  Daily Telegraph 18/07/2019

The question of scale 

There are many in the sector who are committed to broadening access to independent schools. There is a clear direction of travel, and we all recognise that there is a long way to go. 
According to figures from the Independent Schools Council, 176,633 students (34%) received some help with their fees. Of these 5998 students (1.1%) last year were in receipt of 100% or more bursary assistance, and a further 11,566 (2.2%) over 75% funding. Critics are wont to focus on the 1.1% statistic, but this is rather simplistic, for bursaries of this nature tend to be awarded to students of secondary schooling age, especially in the sixth form. And it is really the sixth form bursaries that matter because this where independent schools can have their greatest impact. This because the sector is, as we have seen, a more significantly player at this age group; and also because it is the key springboard that provides access to university. 
Again, we need more aggregated data to have an informed debate. We need to know what the proportion of sixth formers are on full bursaries in independent schools and, importantly, what they go on to do after school and where. 
So, for me, the debate here is not whether or not Independent schools are vehicles of social mobility, but whether or not they are so on a scale that is appropriate and acceptable within society. 
Even without access to data, and despite the valiant efforts of the pioneers like Philip Britton and Sue Hincks at Bolton School, there is little doubt that this figure currently is too low. 

A possible way forward . . . 

The annual cost of state education per student in England is £6,000 (Institute of Fiscal Studies 2019 annual report on education spending in England) and £4,900 in the sixth form. The average annual fee for an independent day school at secondary is £15,522 and £15,027 in the sixth form (ISC Census 2019 p.18). 
One possible way forward would be for all parents (below a certain family income threshold?) to choose to be able opt out of the maintained sector and move their funding to the independent school of their choice. 
Such an approach is not new. In 2010, Paul Collier, Professor of Economics and Public Policy in the Blavatnik School of Government, Oxford University, argued that the ban on "blended funding" that causes the "Educational Apartheid" that is the British system of schooling. (Private v state: here's how to bridge the educational divide Independent 14/01/2010
An educational credit or voucher system would provide greater scope for existing independent schools to open their doors wider at no additional total per capita cost to the state. In this context it is possible to conceive of a situation where independent schools offer both a much greater number of bursaries which top up to 100% of school fees; and a significant number of ‘match funded’ bursaries, making private education much more affordable to a wider population.
I believe that the time has come for society to reinstate a mechanism that broadens access to independent schools. Just as the Direct Grant system provided opportunities for all to go to top schools before 1976, so, too, a combination of a voucher and a bursary system could provide the same opportunities for social mobility from 2020.

This article was published on the PSPR Blog (13/01/2020)