State schools are to be allowed to set their own term times, under plans that could signal an end to the traditional six-week summer holiday.
The new Deregulation Bill means local councils will no longer be able to tell their schools when terms should start and end.
It paves the way for individual schools to introduce longer terms and cut the length of school holidays.
The move was announced just weeks after Education Secretary Michael Gove suggested the current school year is out of date and that children should have shorter holidays.
Under the current system, state school pupils usually get two weeks off at Christmas and Easter, six weeks in the summer, and three week-long half term breaks.
School days usually run from around 9am to 3pm, or 3.30pm.
If the proposals are passed, the changes affecting local authority-run schools would come into effect in September 2015.
Academies and free schools - which are semi-independent schools that are not under council control - already have the freedom to set their own term dates.
All state schools will still be required to open for at least 190 days of the year, the Department for Education (DfE) said.
But the decision is expected to face opposition from some teaching unions, who argue teachers and pupils already spend long hours in the classroom.
A DfE spokesman said: "It is heads and teachers who know their parents and pupils best, not local authorities.
"So it is right that all schools are free to set their own term dates in the interests of parents and pupils."
Brian Lightman, general secretary of the Association of School and College Leaders (ASCL) , said: "Deregulation shouldn't be a major issue as a large proportion of schools already have the ability to set their own term dates.
"Most schools choose to follow the local authority calendar because they know that it's better for parents who have children in different schools and teachers who want their holidays to coincide with their children's.
"The problem will come if no one is responsible for creating a co-ordinated calendar for an area and it turns into a free for all.
"Somebody needs to take the lead locally on deciding term dates and it makes sense for this to be the local authority, even if schools aren't required by law to follow it."
In a speech in April, Mr Gove called for longer school days and term times, claiming pupils are at a "significant handicap" compared to youngsters in East Asian nations who benefit from extra tuition and support from teachers.