Schoolboys aged just 11 will be sent on "anti-misogyny training courses" as part of a new Labour scheme to "protect women and girls".
Secondary school pupils in England displaying "worrying behaviour" could be enrolled in the programmes in a pilot scheme which may even be expanded to include primary schools down the line.
The courses would be led by teachers or external contractors alongside normal lessons.
Girls would also be eligible if they display "harmful" behaviour - but Labour's focus is on boys.
Ministers are to unveil the initiative on Thursday as part of a broader strategy aimed at cutting violence against women and girls by half within ten years.
All secondary schools will be required to deliver lessons on healthy relationships.
Teachers will receive specialist training to discuss topics including consent with their students.
A new helpline will offer support to teenagers worried about their own behaviour in relationships.
PICTURED: Sir Keir Starmer embarks on a visit to St Mary Magdalene school in London to meet with young people to discuss issues surrounding violence against women and girls
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Sir Keir Starmer said: "Every parent should be able to trust that their daughter is safe at school, online and in her relationships.
"But too often toxic ideas are taking hold early and going unchallenged.
"This Government is stepping in sooner - backing teachers, calling out misogyny, and intervening when warning signs appear – to stop harm before it starts.
"This is about protecting girls and driving forward education and conversation with boys and young men, which is a responsibility we owe to the next generation, and one this Government will deliver."
LABOUR'S PLANS FOR EDUCATION - READ MORE:
The scheme could even be expanded to primary school pupils in future (file photo)
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The Prime Minister argued that harmful attitudes must be challenged before they become "entrenched".
Taxpayers will be made to fund 80 per cent of the scheme - in total, a £20 million funding package.
The remainder will come through an innovation fund involving as-yet-unnamed philanthropists.
Schools participating in the teacher training pilot will be selected next year.
Ministers want every secondary school in the country to deliver "healthy relationship sessions" before the current Parliament ends.
Research commissioned by the Department for Education found that 70 per cent of secondary school teachers surveyed reported their school had dealt with sexual violence or harassment between pupils.
Paul Whiteman, general secretary of the National Association of Head Teachers, said the new training courses were "something school leaders have long called for".
But Dame Nicole Jacobs, the domestic abuse commissioner for England and Wales, said the commitments "do not go far enough" to see the number of people experiencing abuse start to fall.
She added: "Today's strategy rightly recognises the scale of this challenge and the need to address the misogynistic attitudes that underpin it, but the level of investment to achieve this falls seriously short."
And Safeguarding Minister Jess Phillips said: "For too long the scale of violence against women and girls has been treated as a fact of life in our country.
"I am determined our groundbreaking strategy will prevent women and girls from actually being harmed in the first place.
"Put together, from today, it will deploy the full power of the state to introduce the largest crackdown to stop violence perpetrated against women and girls in British history."
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