Sex education is to be made compulsory in all state schools under plans outlined in a government-commissioned report published today.
Pupils will receive lessons in contraception, pregnancy and sexually transmitted diseases.
The review follows schools minister Jim Knight's announcement last year that children as young as seven would be taught about puberty and the facts of life.
Lessons are to form as part of a wider reform of the Personal, Social, Health and Economic Education (PSHE) curriculum expected to be introduced by 2010 as subjects become mandatory in all primary and secondary schools in an attempt to reduce the UK's high teenage pregnancy rate.
Sir Alasdair McDonald's review into PSHE focused on the best way to make lessons compulsory and whether parents should be allowed to opt-out.
Schools will be able to ensure their approach is "in line with the context, values and ethos of the school", Sir Alasdair said under the reforms Catholic faith schools would be able to teach about contraception but also inform students that it is contrary to their religious beliefs.
In response to the review, schools secretary Ed Balls backed the recommendations on the basis that governing bodies had the ability to shape lessons to local need and parents were able to maintain the right to withdraw children from sex education classes.
Further recommendations included state that children will not face any extra Ofsted inspections and pupil assessments should be informal rather than involving traditional exams.
The schools secretary said: "Compulsory PSHE will mean consistency and quality so all children can benefit.
"I accept the recommendation but propose that we will keep the issue under review to ensure this entitlement is met."
Balls accepted the recommendations, subject to a four-month consultation. He later told the Commons that he expected PSHE to become compulsory as of September 2011.