The idea that top-performing school systems only select the most academically successful to become teachers is a "dangerous myth", a Finnish education academic has warned.
Professor Pasi Sahlberg told the Oppi education festival in New York this weekend that neither Finland nor Singapore take an academically elitist approach to selecting teachers, recognising that under-performers at school could be the best later at explaining ideas to pupils.
England has been among countries that have attempted to emulate high-performing nations in recent years by restricting entry to the profession to those with better degrees.
The Harvard education academic acknowledged that fewer than 10 per cent of applicants for teacher training places in Finland were successful.
But he said that, of the 120 students accepted by the University of Helsinki for teacher training, only a quarter came from those in the top 20 per cent for academic results. Another quarter were in the bottom half.
"Why does the university want to have someone who hasn't got the highest marks in reading, maths and science when there are so many applicants they could easily fill the 120 seats with the best kids there?
"It's because in my country - and also in Singapore, and, as far as I know, in many other places where they are doing well with the teaching profession - the teaching profession is for everybody. It's a completely different idea to saying teaching is only for the best and the brightest who had the highest test scores."
The students with the lower academic results were "the young people who have the heart and mind to pick up teaching but they are not necessarily good students in a school because they've often had something else to do".
"Typically many of those students are the ones that have been doing youth work, sports and arts or community service or something like that and that's why they didn't go to school properly. But they can explain - and that's what makes them good teachers."
Professor Sahlberg said teacher education in Singapore took the same approach, although he had yet to obtain comparative data.
He said he feared that young people with the right skills would be put off going into teaching if it were only for the academic elite.
"That's why this myth, that we only select the best and the brightest, is a dangerous one. It's changing the whole idea of what it is to be a teacher."
The former education secretary Michael Gove cited Finland when he first announced plans to try to raise the entry bar to teaching in England. Since 2012 teacher training organisations have faced targets for the number of trainees with a 2:1 degree or above.
Teach First, and the global Teach for All movement of which it is part, has also placed a major, public emphasis on recruiting the academic elite.