At an international conference promoting Britain's workplace qualifications, Mr Blunkett called for a more flexible approach to the 14 to 19 age range.
He said students must be persuaded to mix and match academic and vocational qualifications, even if they were high-flying GCSE and A-level candidates.
"We need to be imaginative. We need to challenge this old-world obsession with the professions promoted by people who don't want to get their hands dirty, " he said.
The Government is already promoting diversity in sixth-form studies through its consultation document on the future of 16 to 19 studies.
But this week Mr Blunkett made it clear that he wants flexibility from key stage 4 (age 14) onwards. A number of opinion-formers, including Qualifications and Curriculum Authority chief executive Dr Nick Tate, have already called for a GCSE rethink.
Last month the organisation for leading public schools, the Headmasters' and Headmistresses' Conference, called for its abolition.
Mr Blunkett was speaking at the launch of British Training International, a new Government-sponsored company which is charged with marketing national vocational qualifications to foreign institutions.
The initiative was recommended by the Beaumont report on vocational qualifications. NVQs are to be marketed abroad, despite criticism of them at home.
At the launch, the new BTI chief executive Ruth Gee argued that the quality of expertise on offer from British education and industry will outweigh domestic arguments about workplace training.
But she accepted that a more positive outlook among British educationists would be a significant advantage to the new company.