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Councils have claimed a key government youth scheme is not value for money.
The National Citizen Servicea four-week summer initiative for 15 to 17-years-oldscost the government £634m between 2014/15 and 2017/18.
That amounts to 95% of central government spending on youth services over the period. But the Local Government Association said only 12% of eligible teens took part in 2016.
The government said the service has improved 400,000 young people's lives.
It also said it was investing another £80 million on youth projects.
But the LGA said it was "wrong" that funding was tied up in one "very short programme".
The money should instead be given to local councils, who could then provide "all-year-round provision for young people", it added.
The LGA represents 370 councils in England and Wales. The citizen service runs in England and Northern Ireland.
A 2012 BBC report on the NCS
The NCS was launched in 2011 by David Cameron as part of his "Big Society" project.
Now open to teenagers between the ages of 15 and 17, the NCS is a four-week programme that runs in local communities during the summer.
Volunteers take part in outdoor activities such as rock climbing and canoeingwhile also working on community projects and learning skills such as money management.
Funding cuts have led councils to cut their spending on youth services from £650m in 2010/11 to £390m in 2016/17, the LGA said.
It also said more than 600 youth centres had closed between 2012 and 2016.
Anntoinette Bramble, chair of the LGA's children and young people board, stated that while the NCS was a "good programme", the government needed to "provide targeted support to a much wider group of young people".
This is not the first time the NCS has faced calls for change.
In 2017, the Public Accounts Committee (PAC) said it "may no longer be justifiable" to keep the NCS going unless costs could be brought down.
The PAC report added that the Department for Digital, Culture, Media and Sport, which has overall responsibility for the scheme, lacked the data to "measure long-term outcomes of the programme or understand what works".