Peers are being asked to back moves to give parents legal rights to protect children from "explicit and unacceptable" sex education.
And Brighton and Hove City Council and East Sussex County Council are being used as examples of authorities which use the teaching methods which have sparked concern.
Conservative Baroness Blatch fears youngsters will be exposed to inappropriate teaching materials.
In advance of the crucial free vote in the Lords during the Report Stage of the Local Government Bill, Lady Blatch has put on a display in the House some of the teaching methods she fears and is asking peers to back her amendments.
One example is a booklet called Taking Sex Seriously, published by Healthwise.
Intended for children as young as 11, it gives details of sexual activities including sadomasochism, the use of pain, dressing up, tying up, multiple partners and partner swapping.
Lady Blatch told a Westminster news conference her solution was a series of amendments which extend parents' rights to cover any sex education.
She warned sex education was creeping into other areas of the national curriculum, which meant pupils could not be withdrawn from lessons by the parents.
Lady Blatch said parents who took their duties seriously, did not want this type of education for their children and added she had received a huge mailbag on the subject from members of the public.
"They are writing heart-felt letters, grannies, mothers fathers - even some children," she said.
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