Over the course of St. Mary's College's history, one activity has stayed and progressed with the school, even to this day. Initially, there was only one scout troop in St. Mary's College, the 1st Trinidad Sea Scout Troop, which did not get much competition from the other activities in the College, however, this soon changed.

On the sixth of November, 1936, another troop in St. Mary's was officially founded. This troop was founded by Fr. Toba Valdez (a former 1st Trinidad Sea Scout member, a teacher of the College and a Holy Ghost Father) with help from Mr. Hue Marzley. Together, they built the foundation for one of the most popular activities, not to mention scout troop in St. Mary's College.

Initially, the troop was quite small and consisted of Catholic students only (at the time, the school was predominantly Catholic). The troop started with one patrol whose members were to become the first patrol leaders (PLs) of various patrols. Since the troop was a sea scout troop, its members were taught to swim, to row, as well as normal land scouting activities like camping and knot/rope work. During the school vacations, the scouts would go on a camp at Maris Stella. Maris Stella, built during Fr. Valdez's reign, is a scout house located on the island of Gasparee just off Chaguaramas. The troop also held weekly meetings at our Boat House in Cocorite to discuss anything affecting the troop.

In 1985, Fr. Toba Valdez retired due to ill health, but was replaced by yet another Holy Ghost Father, Fr. Ronald Mendez. Fr. Mendez kept most of the traditional activities except for a few adjustments and inclusions. Scouts were now taught life-saving techniques during swimming sessions, held at the schools pool in St. James. Meetings were now held in the school; and kayaking and sailing were included in the scouting program.

Five (5) years after accepting the role of troop leader, Fr. Ronald Mendez had to resign. His successor came in 1990. Mr. Andrew Buckmire who is still our troop leader and is affectionately referred to as 'Buck'. A few years ago Mr. Hamilton became Buck's aid. They continued with the regular scouting program adjusting it a bit. They did a very good job of taking charge of us scouts. After only a brief stay of a few years, Mr. Hamilton had to leave the troop, leaving the enormous responsibility of managing the now expansive troop to Mr. Buckmire alone. Mr. Buckmire received some help from Mr. Gregory Lee Kin, who as of April 2006 became an Assistant  Scout Leader, and also got another assistant - Mr. Peter Yip Young. Mr. Buckmire, still largely depends on the help of mature enthusiastic scouts to run the troop.