THE only Spaniard out of 20,000 candidates and 179 countries will be on edge this weekend as he waits to hear whether he has won the Global Teacher Prize 2017 – and the €1 million in cash that comes with it.
David Calle worked at a remedial studies academy to pay his way through university when he was studying engineering, and when he became unemployed years later, started his own, similar school.
But he was worried that he was unable to help students outside of the classroom – when they most needed it – and about the fact that many students' parents could not afford the academy fees or a private tutor.
So, he started uploading his lessons onto YouTube and, six years on, has over 700 videos about maths, chemistry, physics and IT, which have attracted over 700,000 subscribers and 100 million hits.
As well as Spain's largest distance education resource, David Calle's series of video classes, the UNICOOS series, were named as the channel with the greatest social impact in Spain by Google in 2015.
Five- and 10-minute sessions cover maths and science subjects for pupils from first year of high school to sixth form and beyond, explaining them in a clear, no-nonsense fashion whilst demonstrating them on a whiteboard.
Students who have used his clips for revision and to clarify key areas say his methods are so accessible that almost anyone could get through exams in his subjects with the help of Calle's explanations.
The Global Teacher Prize is considered to be the 'Nobel of the education world', and the winner will be announced this Sunday, March 19 at an awards ceremony in Dubai, UAE.
Calle is the only Spaniard in the running, but the other 19,999 candidates come from a further 178 countries, including the UK, Germany, Australia, Canada, Kenya, Jamaica, Brazil and China.
“Thanks to this guy, I passed my Bachillerato [Spain's answer to A-levels], so I'm eternally grateful to him,” said one young woman.
Another said Calle and his classes were a million times better than his teachers at high school and enabled him to pass the maths element of his Bachillerato, which he had more or less been told he would fail.
Others who have returned to studying decades after leaving school say they remember teachers who – unlike those in today's classrooms – had no idea how to motivate pupils and 'were only capable of dictating', in both senses of the word.
“There were times when we spent the whole morning copying down notes from the blackboard without really knowing what we were writing about; but David Calle tells it in a way anybody can understand,” said another mature student.
Photograph from David Calle's YouTube classroom channel, UNICOOS