In a keynote speech, the Prime Minister called on state schools in England and Wales to learn from the independent sector and to do more to help gifted pupils.
"We want first-rate secondary education for all, with the excellence and flexibility within every school to make the most of every pupil," Mr Blair said. "Let's be clear what this means. It means a big change from the old comprehensive model."
He called for more setting and "personalised provision" for pupils and criticised the Right for "exclusivity" and the old Left for obstructing talented children.
Phil Willis, the Liberal Democrats education spokesperson, said the Prime Minister's comments were "a condemnation of his own Secretary of State's attempts to dictate to schools when to teach, what to teach and how to teach."
John Dunford, general secretary of the Secondary Heads Association dismissed Mr Blair's comments as a "caricature" of the state system and said his description of secondary schools was "not based on reality".
Mr Dunford also hit the headlines with warnings over the new sixth-form curriculum, which is being taught for the first time this term.
While he stressed that most heads are in favour of the broader programme for A-level, Mr Dunford warned that pupils now faced working an average 50-hour week. He said that this was an "inevitable consequence" of ministers' decision to keep the same standards but increase the number of subjects students studied.
Meanwhile, the largest headteacher's union, the National Assocation of Head Teachers announced that it was advising its members to "go slow" on red tape-related workload.
The advice to drop any task not directly related to educating pupils or running schools is a protest against the Government's failure to reduce bureaucracy and follows the announcement in June of a work-to-rule over the same issue by the National Union of Teachers and the National Association of Schoolmasters Union of Women Teachers.
However, the association, along with most of the other teaching unions, was happy to endorse the Government's launch of three new booklets for parents designed to involve them in schooling.
The Learning Journey guides to the national curriculum cover every year from pre-school to the end of GCSEs and include "top tips" such as how to use junk mail to improve reading. They are part of a Government drive to harness parents' teaching power. There will also be a magazine and an Internet site to support parents.
Parents in Scotland would probably settle for a reliable exam assessment system as the chaos continues. About 1,000 teachers are to be taken out of the classroom to deal with 125,000 appeals to the Scottish Qualifications Authority. The authority has pledged to deal with all urgent appeals by September 20.
But the biggest cause of chaos this week was farmers and lorry drivers who blockaded oil refineries. Some school bus services were cancelled and the NAHT advised concerned schools to prepare themselves, as pupils may end up stranded at home.
Rhondda Cynon Taf County Borough Council in south Wales said it would close its 19 secondary schools from Thursday due to the crisis.