The Conservatives announced their election manifesto yesterday, pledging to allow parents to set up their own schools.

The same approach has been adopted in the US and Sweden, with mixed results.

Tim Harford, Radio 4's More or Less presenter and Today programme number cruncher for the election, and Mike Gibbons, chief executive of the Richard Rose Federation which runs some academies, examine the pros and cons of charter schools.

Get in touch with Today via email , Twitter or Facebook or text us on 84844