The school's Head of History, Susan Casey, says it is a remarkable find.
She is hoping money can be raised to conserve the shelter and turning it into a teaching facility.
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Our Sunderland fan blogger gives their assessment of the club's defeat at Everton
Nicola Sturgeon said the London mayor's comments that likened Scottish nationalism to racism were a sign of 'desperation'.
Stephen was last seen wearing a black coat, jeans, black hat and was carrying a bright blue nike bag.