Crescent completed back-to-back triumphs in the competition for the first time at Clifford Park yesterday.
They had to battle much harder than the final scoreline suggests, however, against an Ardscoil team whose forwards battled gamely throughout.
With No 8 Paul Obande dominating, Ardscoil were the better side in a first half during which neither could manage a score.
Two long-range penalties by their captain Gearoid Lyons, neither of which was successful, was all that Crescent could manage as they were frequently on the back foot.
And when Stephen Fitzgerald opened the scoring with a penalty four minutes into the second half to put Ardscoil in front, the holders looked in trouble.
But champions do not surrender their crowns too easily, and midway through the half came the vital breakthrough for Crescent when winger Alan Crean rounded off a move and beat the cover for a tremendous try, which Lyons converted.
That score sparked new life into Crescent, and it removed all the nervousness that had dogged them earlier on.
Their other winger Jack Hogan bagged try number two and again Lyons landed the conversion.
To assure Lyons of a man-of-the-match performance, the out-half calmly slotted a drop-goal to give his side a 17-3 lead.
Ardscoil were reeling at this stage, and near the end Cormac Blake scored Crescent's third try to give his school the title for the fifth time in their history.
Four of the wining side were also successful in last year's final, and the quartet of Greg O'Shea, James Green, Cormac Blake and Lyons all proved their worth by playing major roles in this success.
Ardscoil were disappointed with the scoreline, but it was certainly not the fault of Obande, Daniel Wixted and Frank Bradshaw-Ryan in their pack.
Half-backs Robbie Deegan and Stephen Fitzgerald also did well, though they could not halt the Crescent bandwagon.
Crescent Comprehensive -- J O'Sullivan; A Crean, G O'Shea, JJ O'Neill, J Hogan; G Lyons, E Barry; J Tuohy, C Rea, L McMahon; M O'Donnell, J Kavanagh; R Noone, J Green, C Blake.
Ardscoil Ris -- B Moriarty; J Walshe, W Leonard, S Fenton, O Lyons; S Fitzgerald, R Deegan; K Browne, K Bracken, J O'Hanlon; F Bradshaw-Ryan, D Wizted; J Cannon, J O'Halloran, P Obande.
REF --O Hodges (MAR).