Baroness Jay, Minister for Women, will tomorrow announce that teenage girls have been identified as a priority area, amid concerns that they are more likely to "drop out" than boys are.
Ministers will set up an advisory group of female high-flyers to act as role models to teenage girls. Ms Halliwell, recently appointed a United Nations ambassador and an advocate of "girl power", has expressed interest in joining.
Other celebrities likely to be approached include the actress Emma Thompson and the therapist Susie Orbach. They will work with less well known successful women in arguing that teenage girls should have higher aspirations.
"Role models are very important in the development of teenage girls," Lady Jay said. "We are trying to create a group of people we can use to be that." Ministers also plan to send girls on "awaydays" where they will be able to discuss issues such as sex and drugs with professional counsellors away from the classroom.
Teachers will be asked to identify school-leavers who have successfully made the transition to work who can attend as well. Members of the "role model panel" could be invited. "It's no good having a teacher who teaches geography in the morning and contraception in the afternoon," Lady Jay said. "We want to take it out of that context."
The Government has been prompted to act by research showing that girls out-perform boys during their early school years, then fall behind. Ministers are worried about increasing drug and alcohol abuse among girls, and the rising number of "girl gangs".
The drive to tackle problems among girls is part of a wider initiative to help women. The women's unit, set up by Harriet Harman last year and being relaunched tomorrow, has been moved to the Cabinet Office.
Lady Jay wants to replace old style feminism with an attempt to tackle bread-and-butter issues that concern women, such as income, health and education.
She would not describe herself as a feminist, she said. "In politics, feminism is seen as negative, complaining about things; it's perceived to be about separateness, putting up a brick wall between men and women. I don't think you have to be negative like that."
Ministers and officials will be sent a document this week that tells them to vet all proposals for their implications for women, members of ethnic minorities and disabled people. It is signed by Lady Jay, Jack Straw, Home Secretary, and David Blunkett, Education and Employment Secretary.
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