Every Government department should be "constantly pushing" to improve the lives of children to ensure they do not become the "lost generation", England's new children's commissioner has said.
Dame Rachel de Souza, who ran a trust of 14 schools in Norfolk and Suffolk until she took up the post last month has called on the Prime Minister and Chancellor to include children in every speech and ensure that childhood is "right at the top" of the Government's agenda.
The new children's commissioner for England is launching a "once-in-a-generation" review to reach every child and identify any barriers preventing them from reaching their full potential amid the pandemic.
Dame Rachel, who was chief executive of The Inspiration Trust said:
The review, titled The Childhood Commission, aims to address policy shortfalls that have held back the lives of children for decades, as well problems that have been amplified by the pandemic, the commissioner said.
Dame Rachel told the PA news agency that she was "absolutely determined" to make sure that children are prioritised so they do not become the "lost generation" as a result of the pandemic.
The children's commissioner is aiming to ask every child in England how the pandemic changed their lives, what their aspirations are and the barriers to reaching them, how things are at home, how their communities could be improved and how they feel about the future.
A study from NHS Digital shows that one in six children in England aged five to 16 reporting having a probable mental health disorder in 2020, up from one in nine in 2017.
Education Secretary Gavin Williamson has said a change to the summer holidays and longer school days are being examined as part of long-term recovery plans for helping pupils catch up with missed learning.
On proposals to change the school calendar, Dame Rachel told PA: "I think it's really interesting. When I was running a trust myself, it was the children themselves who wanted to come back to school and wanted to come back to school early in the summer holiday so they didn't miss out."
She added that lots of schools already run "longer school days in ways that work for their communities".
Dame Rachel said: "So I think we should be exploring these ideas with headteachers, with parents, with children, but for me, as children's commissioner, my job is to ask children and young people what they think and to share that. So hence, that's why we are doing 'The Big Ask'."
An online survey will be distributed to all schools as part of consultation - which will take place after the Easter break - and it will also be sent to youth custody organisations, CAMHS inpatient units and children's homes.
The children's commissioner added: "I want to see a 10-year-plan and I want it to be a plan that really puts children at the centre of all areas of policy so they can have successful lives."
The Commission will be inspired by the ambition of William Beveridge's report in the 1940s, which laid the foundations of the country's welfare state.
Mark Russell, chief executive of the Children's Society, said: "The scale of the challenge is huge and we need to be big and bold. Ultimately, it's up to the Government to deliver change through an ambitious agenda for children and young people, and we hope their intention for putting children's wellbeing first as we emerge from the Covid crisis are not just warm words but lead to tangible action."
A Government spokeswoman said: "We know that children and families have faced unprecedented challenges during the pandemic. We've expanded frontline charity support and provided new resources for schools and teachers to support children and young people's mental health, as well as training from experts to overcome any anxiety or trauma as they return to the classroom.
"Our £1.7 billion investment in recovery support will help tackle the impact of any lost learning and we are investing an additional £79 million to increase the number of mental health support teams working with schools and colleges."