Bexley Business Academy, designed by architect Norman Foster and operated by 3Es Enterprises, will be taking pupils from nursery to A-levels on the same site.
The£10m project is an important step in Tony Blair's attempt to draw private enterprise into the public education system. 3Es already operates three state schools.
Ministers hope for a dozen similar city academies in the next two years, but sponsorship has been hard to find. The bulk of the money for Bexley Business Academy has come from Bexley LBC and central government, but David Garrard, founder and chairman of the Minerva property group, has donated£2m.