Image caption The geographer's study looked at the changing population of England's secondary schools

The number of ethnic minority pupils in England's secondary schools rose by 57% in a decade, according to research from King's College London.

The study by Chris Hamnett looked at the changing demographics of schools between 1999 and 2009.

In inner London, 67% of secondary pupils are from ethnic minorities, says Professor Hamnett.

Gathering such data is important for understanding the future make-up of the population, he says.

The study, from the geography department of King's College London, reveals a "very substantial" shift in the population, which Professor Hamnett says represents an "irrevocable" change.

Changing places

The 57% increase in ethnic minority pupils contrasted with an overall secondary school population rise of 4.7% - and a slight decline in white pupils, a figure that also includes migrants from eastern Europe.

Across the country, the proportion of ethnic minority pupils has risen in a decade from 11.5% to 17% - and Professor Hamnett forecasts that it is set to rise again to 20%.

He found a pattern of an increasing proportion of ethnic minority pupils in big cities, particularly London.

"London as a whole now has an ethnic minority dominated secondary school system, akin to that of many large US cities, and the figure reaches 67% in inner London," says Professor Hamnett.

"This is also true of a small number of other towns and cities with large ethnic minorities, notably Slough (64%), Leicester (58%), Birmingham (52%) and Luton (51%). Manchester and Bradford are not far behind with 43%."

Professor Hamnett says that this is not about recently arrived children, these are children born in England.

And patterns of birth rates indicate that the proportion of ethnic minority pupils will increase in the next decades.

Such changes have become a lasting feature of the ethnic make-up of England's population, he says.

But he also says it shows a picture of ethnic minority families moving out to towns and suburbs across England.

"We're not looking at minorities being trapped or ghettoised in small areas. There's a process of suburbanisation," says Professor Hamnett. This was particularly the case for Asian families, he says.

Among the biggest increases were areas such as Merton, Croydon and Enfield.

New majority

There are also wide differences in the ethnic breakdowns of schools in different parts of the country.

In places such as Knowsley, Cumbria and Durham, fewer than 2% of pupils are from ethnic minorities. In Brent, Tower Hamlets and Newham in London, the figure is above 80%.

Such changes will also eventually mean "revisiting" the language of minorities and majorities, he says.

This relationship between schools and ethnicity has many sides - with wide variations in achievement between different groups. White working class boys have been identified as particular underachievers.

The relatively high performance of schools in inner London has been attributed to the impact of ambitious immigrant families.

Professor Hamnett says it is important to gather such objective data showing the population in schools - which will become the future adult population.

"Let's have the evidence, even if it is politically difficult," he says.

"If we're interested in addressing inequalities in education and access to university, it's only possible if we have gathered the data.

"Once a society stops talking about this, it's the worst kind of self-censorship."