When Tom Ravenscroft left Oxford university with a degree in econ-om-ics and management in 2007, he wanted to be a management consultant. He even had a job offer from Oliver Wyman, following an internship. “I had no career vision beyond going into business. It was a very hazy concept,” he says.

At the last minute he opted instead for Teach First, the educational charity that has become the UK’s biggest recruiter of new graduates. Rather than parachuting into companies that needed restructuring, Mr Ravenscroft started teaching business and economics at Cardinal Pole School, which serves 11-19 year old boys and girls in Hackney, east London.

His strategic shift away from corporate strategy was in spite of the fact that his own school had deterred him from making a career in education, even though he had worked as a private tutor.