The Liberal Democrats have announced plans which would see all children in English state-funded schools receive sex and relationships education from the age of seven.
The party says the "age-appropriate" classes would make up part of a "curriculum for life", which would also feature lessons about money management and citizenship.
The plan would mean that personal, social and health education (PSHE) is compulsory in all state-funded schools including academies and free schools.
Sex and relationships education is compulsory in local authority-run state secondary schools, but not in academies or free schools.
A report published by Ofsted last year found that sex and relationships education needed to be improved in more than a third of schools.
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