Pupils who are due to sit GCSEs and A-levels next summer will be given advance notice of the focus of some examinations to try to mitigate for learning lost as a result of the pandemic, according to plans unveiled by the government.

Ministers have already stated their intention that exams should go ahead in England next summer, but under proposals published on Monday schools will be given some choice over topics in a number of GCSE subjects, in recognition that many students will not have not had time to complete the whole curriculum because of lockdowns and self-isolation.

Pupils will also be allowed support materials, like a formulae sheet for GCSE mathematics, while those facing GCSE physics and combined science will be provided with an expanded equations sheet. There will also be adjustments to science practicals and art and design assessments.

The proposals are now the subject of a consultation and plans will not be confirmed until the autumn term is already under way. Worried school leaders warned the government was “way behind the curve” and expressed concern that there were still no contingency plans in case exams have to be cancelled for the third year running.

“In reality, all of this should have been put to bed weeks, if not months, ago,” said Nick Brook, deputy general secretary of the NAHT school leaders’ union. “We are only days away from the end of term.

Kevin Courtney of the National Education Union said the consultation is being launched ‘far too late’.

“School leaders wanted decisions for adaptations and contingencies made before the summer break, with details before the start of term in September, not least because August will be a busy month supporting students with their results and working on reviews and appeals.”

Under the new proposals, schools and colleges will be given some choice about the topics on which their students are assessed in GCSE English literature, history, ancient history and geography. Exam boards will also be required to provide advance information about the focus of the content of exams at AS and A-level.

Ofqual, the qualifications regulator in England, and the Department for Education are simultaneously consulting on proposed changes to vocational and technical qualifications, which would enable colleges to streamline assessments and provide revision guidance.

Simon Lebus, Ofqual interim chief regulator, said: “With things slowly returning to normal we are launching a consultation so that the flexibility we are building into qualifications will future-proof them against any public health crisis.”

Kevin Courtney, joint general secretary of the National Education Union, warned: “With grim predictability, the government is launching a short consultation in the dead of summer on an absolutely vital issue – this time on exams for next summer … this is already far too late.”

Julie McCulloch, director of policy at the Association of School and College Leaders, added: “We are very concerned that the consultation does not include proposals for a contingency plan in the event that exams cannot go ahead in 2022.

“The last thing we want to see is exams cancelled again but given what has happened this year and last year it is simply a matter of common sense and prudence to map out a contingency plan at this stage.”

The education secretary, Gavin Williamson, said: “Exams will always be the fairest way to assess students, which is why they will take place next year, but it’s right that next summer’s arrangements take into account the disruption young people have faced over the past 18 months.”