Academy chief Dame Rachel de Souza is set to be announced as the next children's commissioner, Tes understands.
The chief executive of Inspiration Trust would replace Anne Longfield, who has been in the role for six years, when her term finishes early next year.
Dame Rachel, who has been a high-profile figure in education during the past decade, would become the fourth person and first serving school leader to take on the role.
Commissioner: Anne Longfield's campaigning role
She is currently the chief executive of Norwich-based Inspiration Trust, which runs 14 schools.
Dame Rachel was the founder of the Parents and Teachers for Excellence organisation, which campaigns for traditionalist education, and is also a trustee of the Ambition Institute.
Academy boss expected to be new children's commissioner
She became a Dame in the 2014 New Year's Honours list for services to education.
This afternoon she has confirmed that she is being nominated to be the next children's commissioner.
She said: "It is a great honour to be nominated for the role of children’s commissioner. Throughout my whole career, I have been a passionate advocate for children and young people from disadvantaged backgrounds and finding ways to support them so they can realise their potential and flourish.
“We all know just how difficult Covid-19 has been for families up and down the country, and – subject to the appointment being approved – I would very much like to play my part in helping to level up opportunities for children, and ensuring their welfare, everywhere, as we come through this difficult time and look towards a more positive future."
In a recent speech to the Schools and Academies Show, she said that the debate within teaching between traditionalist and progressive approaches had become "increasingly dogmatic" and polarising.
She told the online event that the debate had helped to develop her academy chain's thinking but said that there was now a need to "cut through" the conflict and move beyond it.
Dame Rachel was also among the high-profile academy leaders who criticised Ofsted's new inspection framework earlier this year.
She backed comments made by Sir Dan Moynihan, the chief executive of the Harris Federation, and Martyn Oliver, the chief executive of Outwood Grange Academies Trust.
The trust leaders said that the watchdog's curriculum-focused inspections were a "middle-class" framework that would not work for schools serving deprived communities.
The role of children’s commissioner was created by a Labour government 15 years ago to promote the rights of children.
Ms Longfield was appointed to the role in 2014 by the then education secretary Nicky Morgan.
Before this, she had been the chief executive of 4Children, a national charity that works to support children, young people and families.
The first children's commissioner was Sir Albert Aynsley- Green and he was followed by Dr Maggie Atkinson.
During her time in the role, Ms Longfield has campaigned on education issues including off-rolling and school exclusions.
Ms Longfield told Tes last year that the government should investigate schools with high exclusion rates, and she has urged it to intervene at schools involved in off-rolling.
During an appearance before the Commons Education Select Committee, she said that Ofsted and the Department for Education should tell schools that it is not acceptable to put children in “intolerable” isolation booths.