Mr Rennie (70) told staff and pupils yesterday of his decision to retire at the end of the year. It came after he said last year he was looking at retirement when he stood, unsuccessfully, for the Otago Regional Council in the local body elections.
Mr Rennie, who has been OBHS rector for 14 years, said he had mixed feelings about retirement.
''I've really enjoyed my job. This is a great old school and the people here are very good to work with.''
As an old boy of the school, returning as rector was a ''strong desire'' of his.
''I am very privileged to have held it.''
Despite this, he was very pleased with his efforts to change the culture of the school.
''In my opinion, we have made progress on cultural change.''
While still putting all his energies into the school, he was looking ahead, as he did not plan to take things quietly.
He was about to be sworn in as a justice of the peace, had taken on more responsibility at Rotary and was also looking at ways he could ''play a part'' in assisting principals through the Education Ministry.
''I'm not going to just stop. I've always had the opinion if you retire you die and I'm not going to do that.''
The board would soon being looking for a new rector.
Mr Rennie is the third Dunedin secondary school principal to announce they are leaving at the end of the year. Columba College's Elizabeth Wilson will retire after 34 years as principal and St Hilda's Collegiate principal Melissa Bell after seven years.
