David Wootton, Lord Mayor of the City of London, this week visited the Bermondsey academy sponsored by the City corporation and addressed an assembly of 360 pupils from years 7 and 8.
"Everyone starts out with the desire to learn, and the ability to apply what they have learned," the Lord Mayor told pupils.
"Your teachers are equipping you with the tools to achieve great things, and I encourage you to think as big as possible when envisaging your future careers.
"Don't give up, or not try, because you think something is not for you. Because we in the City are rooting for you. And we want to help you achieve success."
The City of London Academy Southwark was the first school outside the Square Mile to be sponsored by the City of London Corporation. The authority now also sponsors academies in Hackney and Islington.
The academy is currently consulting on plans to form a federation with Redriff Primary School in Rotherhithe.