Tries from Cormac Hughes and Niall James in a rampant final 15 minutes saw Leinster claim a deserved victory over Munster at Musgrave Park.
Having been outscored by four tries to one, Munster can have little argument -- the margin would have been greater if Leinster had made better use of their glut of possession after the break.
After a blistering start, Leinster took the lead on four minutes when Sam Gibney bundled over off the back of a rolling maul.
Andrew Carey replied for Munster, darting down the wing unchallenged. Dylan Cadogan added the touchline conversion to give his side a 7-5 lead, but a late Conor Dempsey try for the visitors saw the sides go in at half-time level at 10-10.
With a strong wind at their backs, Leinster dominated the second half, but it took until the 57th minute to press home their advantage, with Hughes dotting down by the posts.
Cadogan's penalty reduced the deficit before James' try sealed the win for Leinster.
Munster 'A' Schools -- D Cadogan (High School Clml); A Carey (Dungarvan CBS), K Desmond (Bandon Grammar), J O'Donnell (Dungarvan CBS), J Donovan (Nenagh CBS); D Kavanagh (De La Salle W'ford), I Daly (CBS Tramore); T Adamakin (Villiers), P Keating (High School Cl'ml), J Reeves (CBS Sexton St); J O'Dwyer (High School Cl'ml), S Carey (High School Cl'ml); B Moore (Midleton College), R Kingston (c) (Bandon Grammar), M Riordan (Hospital). Subs: R Coffey (Mounthawk Tralee), P Traynor (De la Salle W'ford), R Steele (Midleton College), S Scully (Bandon Grammar), B Coady (Villiers), D Finnerty (St Anne's Killaloe), J Barnes (Mounthawk Tralee).
Leinster 'A' Schools -- A Coade (Wilson's H); N James (Newpark Comp), S Bewley (St Columba's), C Hughes (Moyne CS), J Orr (Sandford Park); J Boyd (St Columba's), A Brabazon (Wilson's H); C Dempsey (Good Counsel), S Reamsbottom (c) (Mt Temple Comp),K Browne (Good Counsel); S Gibney (Mt Temple Comp) D Doyle (Ratoath CS); D Carroll (Gorey CS), D Buckley (Wilson's H), A Keating (St Pat's Classical). Subs: A King (Ardscoil na Trionoide, Athy), R Martaise (Wilson's H), R Harrington (Gorey CS), J Salinger (Newpark Comp), T Feegan (Tullow CS), B McDonnell (St Paul's, Raheny), J Wall (Ashbourne CS), M Dolan (St Colmcilles CS).
Ref -- D Noonan (Bruff).