Odorgonno Senior High School (Great OSSA) is a Ghanaian based senior secondary school. Its motto is Nobis Nitendum est, which is Latin and means Ours is to Strive.As of 2017, it has 2,671 students and 183 staff, including 53 non-teaching staff.
The school was established as a boys’ day school in 1940 on the crest of the Odaw River at Adabraka in the Greater Accra Region by Joseph Thomas Leigh and three other teachers at the Accra High School. It was taken into the government system and moved to Awoshie, which is its current location, in 1990. In 1993, it became co-educational, began boarding in 2007, and gained model school status on 25 November 2008.
- George Aggudey, Politician
- Richie Agyemfra-Kumi, Politician
- K.G. Osei Bonsu, lawyer and politician
- Fameye, Musician
- Chris Tsui Hesse, cinematographer, filmmaker, film administrator and photographer
- Bill Okyere Marshall, Playwright
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- Walter Samuel Nkanu Onnoghen, Chief Justice of Nigeria
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- Sheikh I. C. Quaye, Politician
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- Mohammed Adjei Sowah, Mayor of Accra.
- Comedian Waris, Ghanaian comedian
- Guy Warren, Musician, best known as the inventor of Afro-jazz
- Incredible Zigi, Dancer
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