Four fire engines and around 25 firefighters were called to a fire at a school on Amhurst Park in Hackney.
Part of the basement was damaged by fire. Sixty-seven children and 16 adults left the building before the Brigade arrived. There were no reports of any injuries.
Station Commander Sami Goldbrom, who was at the scene, said: "The fire was confined to the basement below the school, which became smoke logged. Crews worked to remove remaining smoke using smoke extractors."
"Thankfully, everyone was out of the building before the Brigade arrived and the school children were sent home."
The Brigade was called at 1337 and the fire was under control by 1420. Fire crews from Stoke Newington, Tottenham, Holloway and Homerton fire stations attended the scene.
The Brigade's Fire Investigators believe the cause of the fire was accidental and involved an electricity meter.