Four key Commons committees are asking the education secretary to make Personal, Social, Health and Economic (PSHE) education compulsory in schools.
The education, health, home affairs and business committee chairmen want PSHE, which covers sex education, made statutory in primaries and secondaries.
In a letter to Nicky Morgan, they express concern at her failure to respond to various committees' calls.
The government is working on a way to achieve high-quality PSHE for all.
It published guidelines on sex and relationship education (SRE) in 2015.
While PSHE education is not part of the statutory national curriculum, which means there is no national programme of study for the subject, the Department for Education say schools should teach it to pupils.
