Sex and relationship education (SRE) is failing millions of pupils. Many will return to school this month to receive mostly inadequate SRE. A survey of teenagers by the Sex Education Forum in 2013 found that a quarter of young people said their SRE was either “good” or “very good”, but slightly more (27%) said it was “bad” or “very bad”. The remainder (48%) rated their SRE as “OK”, well short of a positive endorsement. No wonder Ofsted describes SRE as “not yet good enough”.

For lesbian, gay, bisexual, transgender and intersex (LGBTI) pupils, the quality of SRE is even lower. One in three gay men diagnosed with HIV in 2012 were in their teens or early 20s, yet more than three-quarters of gay and bisexual young people receive no information at school about same-sex relationships or gay safer sex, according to the 2014 Metro report, Youth Chances. These failings border on child neglect, and have prompted a coalition of LGBTI, sexual health and HIV campaigners to this week publish an open letter to party leaders, MPs and the government, which urges that age-appropriate SRE be made compulsory in all schools – and be required by law to address the needs of LGBTI young people. SRE isn’t mandatory at present, and in most cases doesn’t include LGBTI issues.

The signatories, which include Conservative peer Lord Fowler, TV presenter Christian Jessen, the Terrence Higgins Trust, Stonewall, the Lesbian & Gay Foundation, the National Aids Trust and the Peter Tatchell Foundation, stress that shortcomings in most schools are failing the welfare and needs of young LGBTI people and contributing to poor standards of sexual health and mental well-being, including preventable HIV infections.

The letter supports the Sex Education Forum’s campaign, It’s My Right, which is urging the government to guarantee every pupil in every school high quality sex and relationship education. This initiative coincides with the deliberations of the education select committee and a private members bill by Green MP Caroline Lucas, which is scheduled to be debated in parliament next month, with the aim of legally obliging all schools to provide SRE.

Cliff Joannou, editor of QX magazine, who originated the idea of the coalition letter, said: “It’s shocking that in the 21st century schools are still not required to give children and teenagers the education they need to make informed decisions about their sexual health and relationships. In addition, omitting LGBTI relationships from SRE means that too many children and teenagers grow up feeling further alienated by society.”

Kat Smithson, policy and campaign manager at the National Aids Trust, said: ”One in three 16-24-year-olds tell us they don’t know enough to prevent HIV transmission during sex, and at the same time HIV diagnoses amongst young gay men have doubled over the past 10 years. Unless we start teaching young people in school about sexual health and about same-sex relationships then we will only see these numbers increasing.”

So true, which is why I can’t fathom the government’s hesitancy on this issue. Sexual and emotional literacy are just as important as literacy in reading and writing. Education is, after all, supposed to prepare young people for later life. Sex and relationships are a very important part of adulthood. Why, then, is SRE education neglected in so many schools?

All pupils deserve lessons that empower them to make wise, responsible decisions to ensure their sexual health and happiness and to reduce the incidence of unwanted teenage pregnancies, abortions and HIV. Over to you David Cameron.