Putney's new ARK Academy has moved a step close to its £30m renovation after exchanging contracts with developer Barratt.
Barratt are hoping to acquire planning permission for a residential development on a section of the school's site which would generate the funding needed to finance the refurbishment.
The new school opened this autumn and work has already started to provide "purpose-designed, high quality, temporary classrooms".
The school will move into these buildings in February 2013, where they will remain until the renovations are complete.
Some of the renovations will include remodelling internal areas of the main listed building, replacing the antiquated glazing, creating brighter and more spacious classrooms, renewing heating and lighting of the school, building a new four court sports hall to the latest Sport England standards and create a new outdoor multi-purpose sports area re-landscaping the remaining site.
Headteacher Mark Phillips, who has already overseen significant improvements at the school, said: "We are pleased that there has been a further step towards securing the funding which will enable us to create the teaching and learning facilities that ARK Putney Academy's students deserve.
"Our school and neighbourhood community now have a once-in-a-lifetime opportunity to shape the space around us and I would urge pupils, parents, staff and our wider community to get involved in the consultation."
The proposal has caused controversy, with campaigners arguing the plans will see the loss of large section of playground for pupils and the destruction of a listed building.
Public consultations, by both Barratt on their residential scheme and Lend Lease on the renovation of the school buildings, are set to begin soon. Following these initial public consultations, two separate planning applications for the Barratt and Lend Lease proposals are likely to be submitted in the new year.
Once these have been submitted, the Wandsworth Council will consult on the detailed proposals before the planning decisions are made and, if approved, the land sale contract will then be completed.