A stroke of luck saved seven school children from serious injury when part of a ceiling collapsed at a Melbourne primary school on Wednesday. A grade five class of 25 children were sitting on the floor near the front of the classroom, rather than at their usual tables, when suddenly a piece of the ceiling near the windows broke off. Mill Park Heights Primary School principal Deborah Patterson said the youngsters were fortunate the ceiling had not crashed on to them. 'During one of the classes just before morning recess, the girls were on the floor and part of the ceiling actually fell on to the table,' Patterson told Australian Associated Press. 'But because they weren't there, they were working on the ground, the bits that broke off landed a bit on their backs.' Three of the injured were taken to the Royal Children's Hospital wearing precautionary neck braces while another four were taken to the Northern Hospital with minor bumps and scratches. 'All of the other children have been moved to safety and the injuries to the seven that are going to hospital are minor,' Ambulance Victoria spokesman Paul Bentley said. Patterson said the building was only 15 years old and all classrooms would now undergo an extensive check. 