Leinster Under 11s beat their NCU counterparts by 38 runs to take an unassailable lead in their series.
Callum Armstrong (23) and Ryan Keenan (21) were the main contributors as Leinster posted 92.
Luke Crothers (3-9) and Jack Smyth (2-10) were best with the ball for the NCU youngsters.
The visitors reply never got going, as the Leinster bowlers kept a tight grip on proceedings.
Armstrong (2-9) completed a fine match with two wickets, as did Crothers who top scored with 12.
The teams meet again on Friday in the final match of the series, where the NCU will be aiming for a consolation victory.
It's been a busy period for youth cricket with the various regions taking advantage of the good weather.
Under 11 Interprovincial Challenge
Leinster 92 all out (18.2 overs; Callum Armstrong 23, Ryan Keenan 21; Luke Crothers 3-9, Jack Smyth 2-10, )
NCU 54 all out (18.2 overs; Luke Crothers 12, Jack Morrow 7, Callum Armstrong 2-9, Toby O’Connell 1-0, Lorcan Craik 1-4)
Leinster won by 38 runs