From St Mary's College he transferred to Belvedere College, where he was a member of the championship Junior Rugby Cup team, and earned a place on the senior team.
In 1918 he became secretary of the school hurling club which had just been formed, and was one of their most enthusiastic players.

A Jesuit priest, Thomas Counihan, who was Barry's science and mathematics teacher, said of him: "He was a dour kind of lad.
But once he got down to something he went straight ahead… There was no waving of flags with him, but he was sincere and intense."
Notwithstanding his many activities, he did not neglect his studies.
He won a merit-based scholarship given annually by Dublin Corporation, which allowed him to become a student of medicine at UCD.
From St Mary's College he transferred to Belvedere College, where he was a member of the championship Junior Rugby Cup team, and earned a place on the senior team. In 1918 he became secretary of the school hurling club which had just been formed, and was one of their most enthusiastic players.
A Jesuit priest, Thomas Counihan, who was Barry's science and mathematics teacher, said of him: "He was a dour kind of lad. But once he got down to something he went straight ahead… There was no waving of flags with him, but he was sincere and intense." Notwithstanding his many activities, he did not neglect his studies. He won a merit-based scholarship given annually by Dublin Corporation, which allowed him to become a student of medicine at UCD.
Kevin Barry