It's understood 400 pupils had to be led to safety from Catherine Junior School and taken to the nearby infants school at around 2pm.
At its height 46 firefighters were at the scene.
A building inspector from the city council was on the scene to check the safety of the building.
The fire started in the roof.
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Further showers or longer spells of rain for many tonight, heavy at times, particularly over the hills.
Further blustery showers are likely through the night, with these heaviest and most numerous towards the west.