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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Paul Brand and guests - including new North East MPs Anne-Marie Trevelyan and Anna Turley - discuss the Labour/Lib Dem leadership campaigns.
A look ahead at the forecast for the Tyne Tees region.
Health services that dealt with a double murderer should have identified the probability that he would re-offend