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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Duller conditions moving back towards the coast through the morning, leaving a mainly dry day with warm sunny spells.
Showery outbreaks of rain will become more widespread through Thursday with heavy and locally thundery downpours possible.
Pollen: West Midlands Update