When it comes to child poverty, Britain is a country of extremes.
Almost half the children in Bethnal Green and Bow, east London, are classed as poor, while in Aberdeenshire West and Kincardine, in eastern Scotland, it is just over one in 20.
Using newly available data from the Department for Work and Pensions, Danny Dorling, professor of Geography at the University of Oxford and Simon Szreter, professor of History and Public Policy at the University of Cambridge, have mapped child poverty by constituency across the UK.
They wanted to highlight the huge variation across the country - and to demonstrate to MPs that their own constituency cannot be entirely representative.
In future, they hope to encourage MPs from very different constituencies to swap places for a week to broaden their experience. For a list of the top 50 pairings, see below.
Prof Szreter said he had often observed MPs reaching for an example from their constituency to illustrate a particular point or argument.
This is a natural effect of the constituency system, where an MP will develop a close link with their community, through the work they do for constituents.
However, he said: "The problem is we are very impressed in Britain with concrete real-life examples but we rarely think critically about how representative our slice of experience really is and - more to the point - how systematically biased it may well be.
"Our constituency system of representation is not found in many other democracies. It has great strengths of course - the personal accountability to a particular community.
"I think there is a general problem though of the sort we have identified, with wealth and poverty becoming so geographically diversified in our country."
Huge local differences
Their work reveals how in some parts of the country, affluence and poverty sit side by side.
Wyre and Preston North, for instance, has one of the very lowest rates of child poverty in the UK: 6.72% or just over one in 15 children.
Yet in the adjoining constituency of Blackpool South, the rate is nearly one in three - 32.37%.
I visited schools in both constituencies to see what young people thought was important - and to discover what they thought about politics.
South Shore Academy is close to Blackpool's famous pleasure beach.
This was once a thriving tourist district but it's now run down - shops closing, hotels for sale.
There is a high level of youth crime: there are problems with drugs, and homelessness. The constituency has voted Labour for the past 18 years.
In the past, the school has struggled.
Formerly known as Palatine Community Sports College, it was was graded inadequate by Ofsted in 2013.
A year later, it employed former soldiers to improve behaviour.
It is now run by the charity Bright Futures.
In a large, spartan meeting room I asked a group of 15 and 16-year-olds, school parliament members, what local issues a candidate should care about.
Vincent, the head boy, immediately volunteered there was a "huge" problem with drugs in Blackpool.
"I think the best way to combat that would be instead of criminalising people for taking drugs and penalising them, offer them support and help them recover."
Lauren, the head girl, thought there should be more free places for families to go: outings like bowling and laser games were too expensive.
Other teenagers agreed there were few places to go, and young people tended to hang around the streets.
One girl said teenagers felt shunned, saying that "older people tend to cross the road when they see us".
The students were energised as they talked about these issues that affected them, but almost none was at all interested in politics.
It seemed to them remote, nothing to do with their lives at all.
"What is politics?" one asked.
They said they were too busy working to follow the news.
Lauren suggested politics should be taught in school - an idea her classmates supported. I asked if she could explain the difference between Conservative and Labour.
"I wouldn't have a clue," she said. "I just know they're two political parties and that's it."
Labour, the Liberal Democrats and the SNP all support lowering the voting age so that teenagers like these could vote.
I asked how many South Shore pupils would go to the polling station. Fewer than half raised their hands.
Four miles away is the pleasant old market town of Poulton-le-Fylde, in Wyre and Preston North, a Conservative seat.
The price of a 20-bedroom South Shore Hotel will buy a medium-sized detached home here.
Baines School is now comprehensive, but it was founded in 1717 as a grammar and it still has a grand panelled hall, with its own memorial to students killed in World War One.
Baines has four houses, each with its own head boy and girl.
I spoke to these eight pupils in the bright modern school library.
They had all felt the impact of recent exam reform.
They suggested any political candidate should step into their shoes, and understand the stresses on teenagers about to sit their GCSEs. "They need to properly understand the pressures there are at our age," said one.
When I asked about local issues, one girl suggested a new zebra crossing outside the school.
These students could explain the difference between Labour and Conservative.
They watched the news, often at home, discussing it with their parents.
Most thought they should be able to vote.
One girl, Myan, said: "When you're 16 you start paying tax and I think it should be our right to decide what happens to our own money."
All but one said they would vote this time if they could.
This was not a scientific survey, but a snapshot of opinions in two very different but neighbouring constituencies.
Prof Dorling said rich and poor are increasingly living separately in the UK, and that it's becoming less common to find mixed areas in the UK.
He said: "There are only a few very split constituencies with many rich and poor side by side any more.
"That used to be true of central London - no longer."
It is another reason why the two professors are pursuing this project - they hope to invite MPs to swap after the election.