Children could face being at school for nine hours a day and see holidays cut under plans reportedly being examined by the Conservatives.
The proposals, drawn up by David Cameron's former policy chief Paul Kirby, would see school days extended to run from about 9am until 6pm, from the current hours of around 8.30am to 3.10pm. Holidays would also be reduced from 13 weeks to seven.
Mr Kirby told The Sun that it would solve a wide range of issues, "transforming the lives of most households in the UK within two years".
It was suggested the extended days could reduce youth crime, boost education standards and prepare children for the world of work by getting them used to full days. It could also allow parents to return to full-time work.
The Sun said Tory ministers were examining the plans, which would apply to all children in England between the ages of five and 18, in time for the party's 2015 general election manifesto.
Mr Kirby said: "This is a once in a generation reset that wouldn't detract from the current school freedom agenda. It also involves dramatically expanding what schools actually do - into sport and other activities.
"It would also go a long way to solving the crisis around childcare affordability, a major issue for many parents."
A Department for Education spokesman said: "We are already giving all schools the freedom to set the length of the school day and term. Many academies and free schools offer extended opening hours, and we want more schools to take up these freedoms.
"We will obviously consider recommendations for further reforms."