Aberdare Boys' Grammar School was located in Aberdare, Wales. Situated in Trecynon, it was called the Aberdare Intermediate School when it opened in 1896. It was also a mixed school at that time. There were 80 such schools in Wales in 1896, rising to 101 by 1920. The change of name to "Grammar School" followed the 1944 Education Act. In 1964, the school relocated to Cwmdare Road. It ceased to be a grammar school in 1978, when the buildings were used to house the new Aberdare Boys' Comprehensive School.
The school website contains the history of the school together with a considerable number of photographs covering the period 1896 to 1978.