The Government believes that as many as 80 popular schools a year will wish to use its new fast-track expansion scheme to be able to take more pupils.
The policy, highlighted in last month's schools white paper, is part of the Government's aim of introducing a market to education by expanding the best secondaries and speeding up the closure of those that fail.
The fast-track expansion scheme was introduced in August, at the same time as statutory guidance which reinforced the presumption that authorities should approve such plans.
Ministers have also pledged to provide capital funding for building at the expanded schools and are considering whether to extend the scheme to primaries.
Jacqui Smith, the schools minister, asked in a Parliamentary question how many schools she expected to expand under the scheme, said while there was no target, she estimated that some 80 a year might wish to expand. More than 1,300 secondaries are currently full, she said.
When asked a similar question in June, before the fast-track scheme was introduced, she revealed that only 17 had applied.
Ed Davey, Liberal Democrat education spokesman, said: "These figures look to have been plucked out of the air. Even so, they hardly amount to the revolution the Prime Minister was spinning just a few weeks ago. I am sure it will be a lot less as most schools do not want to expand."
John Dunford, general secretary of the Secondary Heads Association, said:
"I think this is probably an overestimate. Although schools are full they prefer to remain at the size at which they have been successful."
WHAT CAN WE EXPECT?
The 2006 education Bill is likely to contain
* A statutory procedure for schools to become trust schools. The Government says this is already possible under a 1998 act, but will bring in new legislation anyway that lays down rules for trusts
* New powers for local authorities to force a failing school to take advice from an external partner or collaborate or merge with a strong school
* A measure allowing schools to use banded admissions but preventing new schools from amending their admissions systems for three years
* Curriculum entitlements for 14 to 19-year-olds as part of the drive to personalise learning
* A right for teachers to discipline pupils
* Extended parenting orders so schools can force parents to take responsibility for pupil behaviour
* A requirement for parents to take responsibility for excluded pupils during their first five days of exclusion
* Measures to make councils identify local children missing from education, take over the role of the school organisation committee, and decide on bids to set up new schools. But councils will lose the right to establish their own community schools