A political historian from The University of Manchester is bidding to solve the mystery of why the UK's colleges of education suddenly disappeared in the 1970s.
Dr Clare Debenham says the colleges, many of which were over a hundred year old, were an important part of the country's higher education system.
According to the researcher, by the end of the 1960s, there were 40,000 students at the colleges compared to 50,000 attending traditional universities.
She said: "The colleges of education were a success story, having doubled in size in response to teacher shortages, extended their courses from two to three years and introduced degree work.
"But in December 1972, Margaret Thatcher, Secretary of State for Education and Science, introduced a government White Paper ironically entitled 'Education: A Framework for Expansion.'
"This proved to be the beginning of the end, but it was a Labour minister, Shirley Williams, who authorised the closure of the colleges of education at the end of the decade."
The official explanation for the closures from ministers and civil servants at the Department of Education and Science, was that the colleges were geographically isolated.
They were also, they argued, not academically respectable and only succeeded in attracting students from a limited range of social backgrounds.
But Dr Debenham, who was herself a lecturer at two colleges of education, says the explanation for the policy of colleges' closure didn't make sense.
She added: "The effects of this change of policy were devastating. In 1970s Manchester, there were nine colleges of education but a decade later they had all been closed, or in Didsbury's case merged with Manchester Polytechnic.
"Were these official explanations 'red herrings'?
"It's very important to collect evidence while people's memories are still clear."
So far Dr Debenham has interviewed a small group of college staff, including Eileen Alexander, Principal of Bedford College who was over a hundred years old, and forty students from twelve colleges.
She would like former staff and students to complete a short questionnaire.
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