Hundreds of schoolchildren in Larne were given the afternoon off for a day in April 1984.
The move came as their teachers took part in a half-day strike for higher wages.
Several local secondary schools were affected when members of the National Association of Schoolmasters and Union of Women Teachers joined the national action.
Nearly 700 pupils were sent home from Larne Grammar School, though the preparatory department of the school continued as normal. About 500 students were also sent home from St Comgall’s and all classes ended at lunchtime for children at Greenland High School.The teachers were striking for a pay rise of 12.5 per cent. At the time they were being offered 3 per cent.Representatives were due to meet in London to try an resolve the issue.There were fears that if the issues continued, pupils who were taking O and A level exams would be affected.