Peers will consider an amendment to the Children and Families Bill, which would make sex education, including lessons on same-sex relationships, compulsory across state-funded primary and secondary schools.
Labour’s amendment, due to be debated later today, proposes that parental withdrawal rights only apply to children aged 15 or younger.
Campaigners in favour of the amendment claim that compulsory sex education can teach boys how to respect girls and tackle violence against women and girls.
In a letter to The Times, campaigners said the proposed amendments, tabled by Baroness Jones of Whitchurch and Baroness Hughes of Stretford, “would ensure that children are taught about sexual consent”.
The proposed changes would also place on teachers a “duty” to teach about civil partnerships and give “information” on same-sex relationships.
Current law requires that pupils are “protected from teaching and materials which are inappropriate”.
Critics of the amendment say it is vaguely worded, requiring sex and relationships education (SRE) to be taught in a way that is “appropriate” to a pupil’s age.
The proposal would abolish the parental right of withdrawal once a child reaches 15 and seriously undermine the role parents play in deciding how much sex education their child is given.
It would also reduce the discretion of schools and teachers and increase the likelihood of children being exposed to unsuitable materials.
SRE would also be taught according to students’ “religious and cultural backgrounds,” while reflecting “a reasonable range of religious, cultural and other perspectives”.
In an article for The Huffington Post, Shadow Home Office minister, Diana Johnson said: “We cannot understand why the government is so opposed to this.
“There is already guidance in place recommending schools teach the broader aspects of sex and relationship education and many schools already do so”.
The amendment would also place a statutory duty on academies to provide SRE, something the Education Secretary, Michael Gove, is opposed to.
The Department for Education said that teachers already have the “freedom to tailor their teaching so it meets the needs of their pupils”.
It said a Government review had concluded that “the existing guidance offers a sound framework for sex and relationship education in school”.