Up to six secondaries will begin next autumn to test how best to give staff long-term help. Self-confidence is important in talking about sex in the classroom.

But there will be no fresh approach to sex education. Research shows schools are already being successful in delivering information and advice, Stephanie Allison, manager of the Healthy Respect project, said.

Boys between S2 and S4 are a key target as studies reveal that one in three relies on schools for information about sexual relationships. Around 35 per cent of 15-year-olds say they have had sex, compared to 26 per cent 10 yearsago.

The pound;3 million, three-year scheme is run by Lothian Health Board and covers several approaches in school and out to improve the knowledge and decision-making of young people.

It aims to cut the incidence of unsafe sex and help to prevent the high rate of teenage pregnancies, which has risen among under-16s by 50 per cent since 1995.

Ms Allison said any further good practice established in the project could be passed on.

“We will be looking at in-service training and whether it makes a difference, and testing methods of support for teachers. For example, we will be looking at co-teaching and peer support, and combined training with other professionals,” she said.

Other priority groups are young people in care, parents and marginalised young people.