Kate Nash's backing track for St Paul's camp

The singer was joined by 30 teenagers, aged between 13 and 17, to record the track yesterday at a former primary school near Old Street Tube station which has been taken over by anti-capitalist activists.

The protesters hope it can be included on an album featuring music from artists such as Ani DiFranco, Tom Morello, and Billy Bragg, who have all pledged support for the St Paul's camp.

The day-long School of Rockupy is the latest incarnation of the Occupy movement and is part of the School of Ideas' Occupy Half Term programme.

It comes after the demonstrators' Bank of Ideas was set up in an empty office block in Hackney, belonging to bank UBS. The group has also taken over a disused courthouse in Shoreditch to hold mock trials, and as well as their St Paul's encampment, are still occupying Finsbury Square.

The event included a number of workshops on songwriting producing, design and marketing, also led by Nash and musician Sam Duckworth, as well as music journalist Dan Martin from NME magazine. Nash, who is writing a new album, said she was more nervous working with the children than performing in front of thousands.

She said: "I do a few of these workshops at different schools but I get much more nervous than performing I get really nervous but I love it."

Spokesman for the group, Ronan McNern, said they had been keen to engage more with the local community with their latest project.

He said: "It will be up to the kids as to what the results will be. With music we can do something really special - create a new way of communicating."

The group are however facing a legal battle to remain in the former primary school, which is owned by Southern Housing which wants to develop the site.

On Tuesday the company secured a possession order at the High Court which is now being appealed against.