Staff were forced to evacuate a secondary school as fire took hold of the building.
Part of Oasis Academy Hadley, in South Street, Enfield, went up in flames on Tuesday (October 22) at 5.43pm.
A total of 26 members of staff inside the building managed to escape before the London Fire Brigade arrived.
There were no reports of any injures, the brigade said.
Firefighters tackled the blaze until the incident was over at 6.59pm. Part of the external surface on the first and second floor of the building was damaged.
A spokesperson for London Fire Brigade said: “One of the Brigade's 32-metre turntable ladders was used at the scene to support firefighters.
“Control officers received the first of 12 calls at 5.43pm and mobilised four fire engines and around 25 firefighters from Enfield, Chingford, Woodford and Edmonton fire stations to the scene.
“The incident was over for firefighters at 6.59pm.”
The cause of the fire is under investigation.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here