Tony Blair has said his effort to reform English schools is "hell" but he hopes the controversy will blow over.
Ministers say people should get away from the politics of the debate
Mr Blair was speaking at a seminar for 50 schools, charities and businesses, including Microsoft, who are interested in being involved in new trust schools.
Potential Labour rebels say they still have concerns, despite concessions made by the government this week.
But Mr Blair's spokesman said he was struck "by how united the Cabinet was" in its discussion of the reforms.
The seminar at No 10 will be seen as a clear signal Mr Blair wants to push ahead with plans to involve new external partners, including companies, faith groups, charities, in setting up and running the schools.
Thursday's meeting, similar to one held at the education department last week, was for organisations wanting to form or take part in trust schools.
Mr Blair told them change always caused a lot of controversy.
"Any of you who have ever put through a change programme, either in your business or in your organisation or your school, knows that basically it's hell while it's happening," he said.
"But if it is the right thing to do then it's amazing how afterwards people actually settle down and wonder what all the fuss was about.
"Anyway, I'm keeping my fingers crossed that's what happens in this case."
Critics of the idea fear undesirable outside organisations may become part of the new trusts and insist on subjects being taught a particular way.
Mr Blair's spokesman said the seminar "shows the growing interest from a range of schools and potential sponsors including KPMG, BT and Microsoft".
When asked why private companies should be interested in sponsoring schools, the spokesman said they might want to be "part of the community from which they need a skilled workforce".
Ruth Kelly has offered a compromise
But he said that "the best people to decide the curriculum are teachers".
The spokesman said trust schools will be able to address schools in new ways that will benefit the most disadvantaged in society.
More than 90 Labour MPs threatened to vote against the government's original school reform plans, fearing they could allow selection by the "back door" and set schools against each other.
Ministers are keen to quell the concerns before Labour's spring conference this weekend.
Ms Kelly on Monday offered a compromise package, including a specific ban on schools interviewing pupils or parents when they decide admissions.
She also said local councils would be able to build new "community" schools - something ruled out in the original Education White Paper.
Facing MPs for the first time since unveiling her compromise plans, Ms Kelly said she wanted a system which was "fair and which is seen to be fair".
Former Education Secretary Estelle Morris is among critics saying the government is moving in the right direction but many details still need to be hammered out.
'Trojan horse' claim
The Education Bill is due to be published later this month, with a vote of MPs taken in March.
The National Association of Head Teachers said the government's concessions provided "important safeguards".
But it had concerns the plans "will still be a Trojan horse, and used to change the educational landscape, creating a two-tier education system with worse schools and poorer education for our most disadvantaged young people".
The union's general secretary, Mick Brookes, said: "This is not so much a battle over vision and reform as a battle for survival of a government that has clearly lost its way with its keynote policy."
Conservative leader David Cameron on Wednesday asked why the government was going "backwards" on education reforms.
Mr Blair denied the accusation, saying he thought Tories agreed there would be no return to selection.