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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Emma Jesson brings you Saturday's forecast for the Tyne Tees region
People have gathered in the city centre to call upon the labour parliamentary party to accept what they Corbyn's 'democratic mandate'.
Officers were informed that the body of a man in his 60s had been found in a property in North Tyneside on Friday night.