The growing crisis over the shortage of school places could see “titan” secondary schools swell to cope with thousands of extra pupils, despite concerns over the impact on children’s education.

As local authorities try to cope with a surge in demand as a result of earlier increases in the birth rate, with those children now moving from primaries into secondaries, one east London council has drawn up proposals for a single secondary school to take in 16 forms of new pupils each year.

Barking and Dagenham’s request to the unnamed secondary school would see it become Britain’s biggest, with up to 2,500 pupils, according to the TES education magazine.

The council, which has asked all of its nine secondaries to consider admitting more pupils, is not alone in resorting to expanding existing schools to cope with the situation. Councils in Birmingham, Peterborough and Slough are also considering major expansions to cope with the “unprecedented” rise in demand.

Official government figures, published last year, project that by 2023 there will be 8,022,000 pupils in England’s schools – up from 7,143,000 in the current academic year, a rise of almost 880,000 pupils.

But education experts have warned that “titan” schools could damage their pupils’ prospects and have called for funding to create new, more modestly sized institutions.

Professor Alan Smithers, the director of the Centre for Education and Employment Research at Buckingham University, has warned: “If you are an 11-year-old who has left a small primary school, to walk into a secondary school with a couple of thousand students, could be very off-putting. It will take some of them a long while to feel known and valued at school,” he told The Independent.

“Education is not just about working towards exams, it is about developing as a person. Many leading schools have rejected the chance to expand because they feel that the optimum size is between 800 and 1,200 students. The answer is to build more local schools.”

Emma Leaman, the assistant director for education infrastructure at Birmingham City Council, said: “The numbers starting secondary school this year are higher than ever, and they will keep rising for at least the next 10 years.”

She anticipated a “substantial appetite among secondaries to expand on their current sites and make more use of existing space”, to bring in extra funding at a time of tightening budgets. “They’re starting to sweat their assets,” Ms Leaman added.

Ruth Bagley, the chief executive of Slough Borough Council, said her town was facing an “unprecedented” rise in secondary pupil numbers and planned to expand three of its 11 schools.

Since 2012, the borough has been trying to create a 64 per cent rise in secondary places by 2022 – an increase in entry forms from 57 to about 95.

Nationally, council leaders warn that by 2018, 60 per cent of areas in England will have a shortage of primary places despite schools going to “extraordinary lengths” and converting non-teaching space into extra classrooms.

A spokesman for the Local Government Association said: “Councils and schools have been doing everything they can to provide places. In all, 300,000 primary school places have been created since 2010 with many schools going to extraordinary lengths to ensure there is a place for every child, including increasing class sizes, diverting money from vital school repairs and converting non-classroom space, such as music rooms.”

The LGA argues that more funding is needed if the necessary 880,000 places are to be created. It estimates that £12bn is needed. The Government’s pledge of £7.35bn for schools leaves a shortfall of £4.65bn.

But a spokeswoman for the Department for Education said: “Significant investment during the last parliament has helped to create half a million new school places since May 2010.