Steve Handford served as a captain with the Royal Regiment of Fusiliers before retraining as an English teacher. He already had an English degree, which allowed him to start a PGCE course. But the transition to the classroom was still not easy.
"When you're in the armed forces you can become a bit institutionalised and cosseted," he said.
Mr Handford, now the northern regional director of the charity Skill Force, spent six years teaching at Monkwearmouth School in Sunderland, Tyne and Wear. He said: "I didn't have problems with discipline, and having been in the services helped me cope with pressure."
Occasionally he would talk about his experiences in Northern Ireland. "I told the pupils how we lost a soldier when a checkpoint was destroyed and the time a helicopter crashed in the base, killing all the crew," he said. "I was not showing off. I told them so they know everyone has dark times and that you have to keep going."