Theresa May is facing calls to imbue a new generation with a sense of civic duty with a programme that would see the young pitch in to help struggling students, care homes, charities and hospitals.

Almost 60 years since national service was brought to an end, a group of 18 charities, businesses and youth organisations has proposed a new programme of voluntary “full-time social action” for those under 30 as a way of preparing them for work and helping public services.

In a letter to the prime minister, the group – which includes the Scout Association – calls for the government to test the idea to see if it would boost the employment chances of young people and help knit together an increasingly divided society.

The group says that governments in Germany, France and the US have already created such programmes, with some attracting more than 100,000 participants each year.

The French president, Emmanuel Macron, has unveiled a plan to bring back national service for 16-year-olds. It will see teenagers choose to spend time teaching or working with charities, as well as the more traditional option of military preparation.

Among the organisations supporting the call for a UK programme are the Association of Colleges, the charity Depaul UK, vInspired, the Wildlife Trusts and City Year UK, which co-ordinates opportunities for full-time volunteering within English schools. The group says that a pilot programme could show that such a scheme would have a major impact on “social mobility, integration, mental health, employability and public service provision”.

“Full-time volunteers aged 18-30 already devote up to 35 hours a week for between three to 12 months to improve the lives of the most vulnerable in our society,” it writes. “Volunteering for charities, they support children to get better grades at school, help people sleeping rough, speed up the recovery of hospital patients and support environmental action.

“Equally, youth fulltime social action is about preparing a young person to enter the labour market. The frontline work experience and careers advice they receive give them the skills and confidence to launch a successful career.”

Former prime minister David Cameron championed the “big society” but some of his initiatives designed to encourage volunteering have run into difficulties. Last year, a Commons committee warned that the National Citizen Service, which backs shorter programmes designed to encourage personal and social development, may no longer justify the money spent on it unless costs could be brought down.

Only 12% of eligible teenagers took part in it in 2016, according to the Local Government Association.

“[Piloting a government-backed scheme] would test our firm belief that a national programme of youth full-time social action would create a much-needed pool of work-ready young talent demanded by employers and educational institutions, as well as benefit the life chances of participants, beneficiaries and, ultimately, the economy. This initiative would also better recognise, support and champion the efforts of young adults leading the way in tackling the great social challenges our country faces.”

The idea of a full-time social action programme for the young was examined earlier this year. However, a report by Steve Holliday, the former chief executive of National Grid, found that “more evidence” was needed before such a government-backed programme could be approved.

Supporters of the idea of a national programme believe that government funding could allow groups to house volunteers and provide more generous support. However, there are unanswered questions about how to fund the scheme sufficiently to ensure that everyone has an opportunity to take part.

Kevin Munday, chief executive of City Year UK, said: “We need 21st-century answers to 21st-century challenges. That’s why we are calling for a new type of national service, fit for the future.

“We know from evidence at home and abroad that full-time social action can play a significant role in tackling issues such as educational inequality, homelessness, loneliness, the social care crisis and climate change. It also provides a platform to give our young people the skills and experience they need to shape and launch their careers.”

Schemes for mandatory community service have been suggested in the past. In the wake of the 2011 riots, David Blunkett, the former home secretary, said such a service should become an “integral part of growing up in Britain, a rite of passage into adulthood, just as national service used to be for the 1950s generation”.

A Department for Digital, Culture, Media and Sport spokeswoman said: “We have received the letter and will respond in due course.”