Letters: Science thrives in all-girls schools It is important to note that this trend is being bucked in all-girls" schools. Girls face external pressures to conform to gender stereotypes, which are stronger in the presence of boys. These pressures can be checked and challenged in an all-girls school, where they have a space in which to develop their full potential, and to make informed but unconstrained choices about interests, subjects and careers. Studies have shown that women who went to girls" schools are more likely to study stereotypically "male" subjects such as maths, physics and chemistry, both at school and university. We know this to be true from our own experience, with girls at the 26 Girls" Day School Trust (GDST) schools and academies over twice as likely to study A-level physics or chemistry than girls nationally, and nearly half the students in GDST sixth-forms taking at least one science A-level. The question is: how can we take this lesson and apply it to all schools? Dr Kevin Stannard, Director of Innovation and Learning, Girls" Day School Trust, London SW1 Economic prosperity could be at risk if more students, particularly females, do not study and successfully complete maths and physics at A-level. Maths and physics are crucial gateway subjects to engineering and vital to industry and the economy. With the Institution of Engineering and Technology's recent Skills and Demand survey showing only seven per cent of the engineering and technology workforce are women, action is needed at an early stage, encouraging females into these subjects. Students are aware of the importance of A-level maths to starting a career in engineering, but the perceived importance of physics is much lower. It is vital that we encourage more students, particularly females, to study these key enabling subjects. Jayne Hall, Policy Advisor, Institution of Engineering and Technology, London WC2 Egypt massacre as bad as crimes of Saddam In the age of the smartphone with its array of apps, world leaders are obviously using the "invisible mummy" filter when checking the newsfeed from Egypt. The hideous sight of hundreds of dead protesters with their bodies wrapped in shrouds should have attracted more than a mild finger-wagging from Obama and Co. The aftermath of the Cairo massacre was apocalyptic, with myriad abandoned shoes and watches only hinting at the scale of the slaughter. Never mind a slap on the wrist and a hissy fit over war games, this was a war crime, as appalling as anything committed by Saddam or Gaddafi. Anthony Rodriguez, Staines, Middlesex I listened with amazement to President Obama's speech on Egypt. His most outrageous statement was telling the world that force is unacceptable, even when national security allegedly trumps personal human rights - nothing is more important than personal freedom. I agree. Would he now like to condemn the Egyptian military for mounting a coup against a democratically elected president? I did not like Morsi's politics and was disappointed when he was voted in. But the essence of democracy is that no matter how unpalatable an elected politician is, the voters, and only the voters, throw them out. Dr Faysal Mikdadi, Dorchester, Dorset Robert Fisk (15 August) made a rare mistake by failing to see the fear that Mohamed Morsi had engendered, not only in Egypt but the rest of the world. Mr Morsi, democratically elected, had started down a path of non-democratic measures. He was restricting freedoms in accord with his party's religious beliefs. He tried to use the mandate of a free election to deliver the removal of freedoms. Vaughan Thomas, Usk, Monmouthshire Debts that will never be repaid Owen Jones ("My message to today's A-level students: seize the future," 15 August) tells us that student loan debt "will leave today's university leavers paying off £60,000 in many cases for the rest of their lives." This overlooks the fact that loan repayments (including interest) are capped at nine per cent on earnings over £21,000, and that any money still due after 30 years is written off. So, this means to a pay a debt of £60,000, you would need to earn £1.3m over 30 years - an average of £43,000 a year. Not many will have that much income, and much of the original loan, and nearly all the theoretical interest, will not, in practice, be paid back. Harvey Cole, Winchester, Hampshire You underestimate the size of the debt graduates now face ("The cost of not gaining a 2:1 degree? Around £80,000," 16 August). For those who do a three-year course with fees of £9,000 a year, their debt on graduation (according to the Government's own calculations) is not £27,000 but £30,723, because the amount borrowed accrues interest. If they also took out a maintenance grant and lived at home while studying (£4,250 a year), the initial debt would be £45,232; if they lived away from home, they could borrow £5,500 a year, producing an initial debt of £49,499; and if they studied in London, they could borrow £7,675 a year, producing an initial debt of £56,924. If they then start on the average salary for a graduate (£25,000), the total repayments if they borrowed £27,000 for the fees would be £57,526; if they took out the maintenance loan too, they would pay back £110,899 if they lived at home, £132,211 if they studied away from home but not in London, and £158,899 if they studied away from home in London. These are the Government's figures against which potential students should assess the costs and benefits of a degree. Professor RON JOHNSTON, School of Geographical Sciences, University of Bristol Northerners do vote Conservative Andy McSmith (12 August) argues that Government welfare reforms "will keep the Tories out of Northern cities for years." I disagree. Of course, as Conservatives, we would prefer to have much more representation in Northern towns and cities, but McSmith's argument assumes that the Coalition policies are more unpopular with Northern voters. I would suggest that as greater numbers move from welfare to work, as a result of an improving economy, they will appreciate the changes that reduce their income-tax burden, freeze council tax and abandon Labour's petrol-duty increases. McSmith seemed to ignore millions of hard-working Northerners and seeks to stereotype them as dependent on the state. The vast majority of my Cleethorpes constituents support the Government's initiative to transform a welfare system that, under Labour, trapped claimants in a cycle of poverty. There is overwhelming support for the £26,000 benefit cap - a figure higher than many of my constituents earn. The Government has also shown its willingness to support the local economy in areas such as northern Lincolnshire and the wider Humber region by investing in infrastructure projects. From Blackpool and Carlisle, through the Yorkshire and Humber region to Brigg and Goole and my own Cleethorpes seat, voters have elected Tories. We were elected to speak up for the North and support policies that will create jobs and opportunities; and we are delivering. Just as not everyone on benefit should be categorised as a "shirker," the impression should not be given that everyone in the North is "welfare dependent." Martin Vickers MP, House of Commons, London SW1 No trouble at Mill for Tories Is Channel 4"s harrowing Sunday-night series The Mill really a historical drama, or a portent of what many Conservatives want to reintroduce in Britain today? I can readily imagine many ministers eagerly viewing the long working hours and lack of employment protection as a wonderful example of "labour market flexibility," while the dangers posed by the unguarded machines would doubtless be venerated as a welcome absence of health-and-safety nonsense and costly red tape for employers. Pete Dorey, Bath Sorry need not be the hardest word Every day we read or hear someone in politics, the media, sports or business make a guarded, hypocritical or self-justifying apology that invites further criticism rather than approval. That is, if any apology at all is forthcoming. So, congratulations to Daniel Emlyn-Jones (letter, 16 August), the field cricket man, who has graced your pages with what must be regarded as a template for how to make a wholehearted and well-reasoned apology. Roger Smith, Ipswich Let there be less light On the 1.4-mile stretch of the A34 between Newcastle-under-Lyme and Stoke-on-Trent there are 10 sets of traffic lights. They interfere with traffic every 246 yards. I think this is a national record. John Ramsay, Stoke-on-Trent Pavement cyclists The answer is, in my experience, "no" because they use the pavement instead. Here, in Bath, I have seen no more than three or four cyclists on cycle lanes in four years; it seems to be far easier to use the pavements and harass pedestrians. Kathy Elam, Bath Long-suffering Before Jeremy Paxman revealed his now infamous beard, I'd never heard of pogonophobia. Does this mean that I suffer from hippopotomonstrosesquipedaliophobia - the fear of long words? Stan Labovitch, Windsor