They will try to show that consultation processes for the new schools are flawed, during three hearings set for the High Court next month.

Lawyer Richard Stein said ministers were "moving the goalposts" in an attempt to have 200 academies by 2010.

The government said the "biggest denial of human rights" was a bad education.

Funding agreements

The High Court is expected to hear challenges to proposed academies in: Merton, south-west London; Islington, north London; and the Isle of Sheppey, Kent.

They focus on claims that rights are being undermined because parents do not have access to "funding agreements", which spell out legal obligations on areas such as admissions, special educational needs and exclusions.

Academies are legally independent and must each come up with their own funding agreement. Some of the parents say this means regular education acts do not apply.

Mr Stein, a partner in the London law firm Leigh Day, which is co-ordinating the cases, said: "There is a whole range of issues concerning parents.

"A number of rights children have in mainstream schools do not exist in academies."

Parents could have less of a say in running academies and there were worries over curriculum content, he added.

'Political imperative'

Mr Stein said: "It feels as if the Department for Education and Skills is making up the rules as it goes along.

"There is a political imperative that they want 200 of these schools in place by 2010.

"They seem to be changing the rules and moving the goalposts in order to achieve that."

Academies - of which there are currently 27 - are intended to raise standards in areas of educational disadvantage.

Sponsors provide up to �2m in capital funding in return for control of the school's governance, to be matched by about �25m from the government which also pays the running costs.

'Flawed'

One of the legal challenges focuses on a claim that an academy in Merton was rushed through even though the predecessor school, Tamworth Manor, was not failing.

An Isle of Sheppey parent contends that the decision to create an academy was taken on a "flawed" basis.

Mr Stein said there were "several" other cases which he expected to come to court.

But a DfES spokesman said: "We totally reject the claim that parents or pupils in academies have fewer rights than those in any other school. The biggest denial of human rights is a bad education.

"Academies promote the rights of children to a good state education where it has not been available in the past. "We do not accept that Academies are exempt from the Human Rights Act.

"Academies are inclusive local schools run in the best interests of the children that attend them.

"There has been no successful legal challenge against an Academy on the grounds that they are breaking the Human Rights Act"